diff --git a/src/defines.h b/src/defines.h
index fe9acf95..21c583b0 100644
--- a/src/defines.h
+++ b/src/defines.h
@@ -13,7 +13,7 @@
 //-------------------------------------
 #define VERSION_MAJOR       0
 #define VERSION_MINOR       8
-#define VERSION_PATCH       7
+#define VERSION_PATCH       0707
 
 //-------------------------------------
 typedef struct {
diff --git a/src/hm/CommQueue.h b/src/hm/CommQueue.h
index 8d0bb0f8..9771393d 100644
--- a/src/hm/CommQueue.h
+++ b/src/hm/CommQueue.h
@@ -85,6 +85,10 @@ class CommQueue {
                 mQueue[mRdPtr].attempts--;
         }
 
+        void incrAttempt(void) {
+            mQueue[mRdPtr].attempts++;
+        }
+
         void inc(uint8_t *ptr) {
             if(++(*ptr) >= N)
                 *ptr = 0;
diff --git a/src/hm/Communication.h b/src/hm/Communication.h
index a4eb43eb..f23fe416 100644
--- a/src/hm/Communication.h
+++ b/src/hm/Communication.h
@@ -11,9 +11,10 @@
 #include "../utils/crc.h"
 #include "Heuristic.h"
 
-#define MI_TIMEOUT      250
-#define DEFAULT_TIMEOUT 500
-#define SINGLEFR_TIMEOUT 60
+#define MI_TIMEOUT      250      // timeout for MI type requests
+#define FRSTMSG_TIMEOUT 150      // how long to wait for first msg to be received
+#define DEFAULT_TIMEOUT 500      // timeout for regular requests
+#define SINGLEFR_TIMEOUT 60      // timeout for single frame requests
 #define MAX_BUFFER      250
 
 typedef std::function<void(uint8_t, Inverter<> *)> payloadListenerType;
@@ -43,7 +44,8 @@ class Communication : public CommQueue<> {
                 if(!valid)
                     return; // empty
 
-                uint16_t timeout = q->iv->ivGen != IV_MI ? DEFAULT_TIMEOUT : MI_TIMEOUT;
+                uint16_t timeout     = q->iv->ivGen != IV_MI ? (mGotFragment && q->iv->mGotLastMsg) ? SINGLEFR_TIMEOUT : DEFAULT_TIMEOUT : MI_TIMEOUT;
+                uint16_t timeout_min = q->iv->ivGen != IV_MI ? mGotFragment ? SINGLEFR_TIMEOUT : FRSTMSG_TIMEOUT : MI_TIMEOUT;
                 bool testMode = false;
 
                 switch(mState) {
@@ -55,11 +57,13 @@ class Communication : public CommQueue<> {
                             mLocalBuf[i].len = 0;
                         }
 
-                        mHeu.printStatus(q->iv);
+                        if(q->iv->radio->isSerialDebug())
+                            mHeu.printStatus(q->iv);
                         mHeu.getTxCh(q->iv);
                         testMode = mHeu.getTestModeEnabled();
                         mGotFragment = false;
-                        mFirstTry = mFirstTry ? false : ( (IV_HM == q->iv->ivGen) || (IV_MI == q->iv->ivGen) ) && (q->iv->isAvailable()); //) || (millis() < 120000));}
+                        q->iv->mGotLastMsg = false;
+                        mFirstTry = mFirstTry ? false : ( ( (IV_HM == q->iv->ivGen) || (IV_MI == q->iv->ivGen) ) && (q->iv->isAvailable()) || (millis() < 120000) );
                         if(NULL == q->iv->radio)
                             cmdDone(true); // can't communicate while radio is not defined!
                         mState = States::START;
@@ -83,12 +87,33 @@ class Communication : public CommQueue<> {
                             q->iv->radio->prepareDevInformCmd(q->iv, q->cmd, q->ts, q->iv->alarmLastId, false);
                         if(!testMode)
                             q->iv->radioStatistics.txCnt++;
-                        mWaitTimeout = millis() + timeout;
+                        mWaitTimeout     = millis() + timeout;
+                        mWaitTimeout_min = millis() + timeout_min;
                         setAttempt();
                         mState = States::WAIT;
                         break;
 
                     case States::WAIT:
+                        if(millis() > mWaitTimeout_min) {
+                            if(!mGotFragment) { // nothing received yet?
+                                if(q->iv->radio->get()) {    // radio received sth.?
+                                    mGotFragment = true;
+                                    if(q->iv->mGotLastMsg) {
+                                        //mState = States::CHECK_FRAMES;
+                                        mWaitTimeout = mWaitTimeout_min;
+                                    }
+                                }
+                            } else if(mFirstTry) {
+                                DPRINT_IVID(DBG_INFO, q->iv->id);
+                                DBGPRINTLN(F("second try"));
+                                mFirstTry = false;
+                                if(!testMode)
+                                    q->iv->radioStatistics.retransmits++; // got nothing
+                                mState = States::START;
+                                break;
+                            }
+
+                        }
                         if(millis() < mWaitTimeout)
                             return;
                         mState = States::CHECK_FRAMES;
@@ -102,7 +127,7 @@ class Communication : public CommQueue<> {
                             DBGPRINT(String(millis() - mWaitTimeout + timeout));
                             DBGPRINTLN(F("ms"));
 
-                            if(!mGotFragment && !mFirstTry) {
+                            if(!mGotFragment) { // && !mFirstTry) {
                                 if(!testMode)
                                     q->iv->radioStatistics.rxFailNoAnser++; // got nothing
                                 mHeu.setGotNothing(q->iv);
@@ -140,7 +165,7 @@ class Communication : public CommQueue<> {
                             DBGPRINT(F(", "));
                             DBGPRINT(String(p->rssi));
                             DBGPRINT(F("dBm | "));
-                            ah::dumpBuf(p->packet, p->len);
+                            ah::dumpBuf(p->packet, p->len, 1, 8, "#"+String(q->iv->id));
 
                             if(checkIvSerial(&p->packet[1], q->iv)) {
                                 if(!testMode)
@@ -178,39 +203,37 @@ class Communication : public CommQueue<> {
                         break;
 
                     case States::CHECK_PACKAGE:
+                        uint8_t framnr = 0;
                         if(0 == mMaxFrameId) {
-                            setAttempt();
-
-                            DPRINT_IVID(DBG_WARN, q->iv->id);
-                            DBGPRINT(F("frame missing: request retransmit ("));
-                            DBGPRINT(String(q->attempts));
-                            DBGPRINTLN(F(" attempts left)"));
-
                             uint8_t i = 0;
                             while(i < MAX_PAYLOAD_ENTRIES) {
                                 if(mLocalBuf[i].len == 0)
+                                    framnr = i+1;
                                     break;
                                 i++;
                             }
-
-                            sendRetransmit(q, i);
-                            return;
                         }
 
-                        for(uint8_t i = 0; i < mMaxFrameId; i++) {
-                            if(mLocalBuf[i].len == 0) {
-                                setAttempt();
+                        if(!framnr) {
+                            for(uint8_t i = 0; i < mMaxFrameId; i++) {
+                                if(mLocalBuf[i].len == 0) {
+                                    framnr = i+1;
+                                    break;
+                                }
+                            }
+                        }
 
-                                DPRINT_IVID(DBG_WARN, q->iv->id);
-                                DBGPRINT(F("frame "));
-                                DBGPRINT(String(i + 1));
-                                DBGPRINT(F(" missing: request retransmit ("));
-                                DBGPRINT(String(q->attempts));
-                                DBGPRINTLN(F(" attempts left)"));
+                        if(framnr) {
+                            setAttempt();
 
-                                sendRetransmit(q, i);
-                                return;
-                            }
+                            DPRINT_IVID(DBG_WARN, q->iv->id);
+                            DBGPRINT(F("frame "));
+                            DBGPRINT(String(framnr));
+                            DBGPRINT(F(" missing: request retransmit ("));
+                            DBGPRINT(String(q->attempts));
+                            DBGPRINTLN(F(" attempts left)"));
+                            sendRetransmit(q, framnr-1);
+                            return;
                         }
 
                         mHeu.setGotAll(q->iv);
@@ -257,8 +280,9 @@ class Communication : public CommQueue<> {
                 return; // CRC8 is wrong, frame invalid
             }
 
-            if((*frameId & ALL_FRAMES) == ALL_FRAMES)
+            if((*frameId & ALL_FRAMES) == ALL_FRAMES) {
                 mMaxFrameId = (*frameId & 0x7f);
+            }
 
             frame_t *f = &mLocalBuf[(*frameId & 0x7f) - 1];
             memcpy(f->buf, &p->packet[10], p->len-11);
@@ -413,9 +437,6 @@ class Communication : public CommQueue<> {
         inline void miHwDecode(packet_t *p, const queue_s *q) {
             record_t<> *rec = q->iv->getRecordStruct(InverterDevInform_All);  // choose the record structure
             rec->ts = q->ts;
-            //mPayload[iv->id].gotFragment = true;
-            uint8_t multi_parts = 0;
-
             /*
             Polling the device software and hardware version number command
             start byte  Command word     routing address                 target address              User data   check   end byte
@@ -458,14 +479,13 @@ class Communication : public CommQueue<> {
                 q->iv->isConnected = true;
                 //if(mSerialDebug) {
                     DPRINT_IVID(DBG_INFO, q->iv->id);
-                    DPRINT(DBG_INFO,F("HW_VER is "));
+                    DBGPRINT(F("HW_VER is "));
                     DBGPRINTLN(String((p->packet[24] << 8) + p->packet[25]));
                 //}
                 record_t<> *rec = q->iv->getRecordStruct(InverterDevInform_Simple);  // choose the record structure
                 rec->ts = q->ts;
                 q->iv->setValue(1, rec, (uint32_t) ((p->packet[24] << 8) + p->packet[25])/1);
-                //mPayload[iv->id].multi_parts +=4;
-                multi_parts +=4;
+                q->iv->miMultiParts +=4;
             } else if ( p->packet[9] == 0x01 || p->packet[9] == 0x10 ) {//second frame for MI, 3rd gen. answers in 0x10
                 DPRINT_IVID(DBG_INFO, q->iv->id);
                 if ( p->packet[9] == 0x01 ) {
@@ -486,19 +506,19 @@ class Communication : public CommQueue<> {
                     //if(mSerialDebug) {
                         DPRINT(DBG_INFO,F("HW_FB_TLmValue "));
                         DBGPRINTLN(String((p->packet[14] << 8) + p->packet[15]));
-                        DPRINT(DBG_INFO,F("HW_FB_ReSPRT "));
+                        DBGPRINT(F("HW_FB_ReSPRT "));
                         DBGPRINTLN(String((p->packet[16] << 8) + p->packet[17]));
-                        DPRINT(DBG_INFO,F("HW_GridSamp_ResValule "));
+                        DBGPRINT(F("HW_GridSamp_ResValule "));
                         DBGPRINTLN(String((p->packet[18] << 8) + p->packet[19]));
-                        DPRINT(DBG_INFO,F("HW_ECapValue "));
+                        DBGPRINT(F("HW_ECapValue "));
                         DBGPRINTLN(String((p->packet[20] << 8) + p->packet[21]));
-                        DPRINT(DBG_INFO,F("Matching_APPFW_PN "));
+                        DBGPRINT(F("Matching_APPFW_PN "));
                         DBGPRINTLN(String((uint32_t) (((p->packet[22] << 8) | p->packet[23]) << 8 | p->packet[24]) << 8 | p->packet[25]));
                     //}
-                    //notify(InverterDevInform_Simple, iv);
-                    //mPayload[iv->id].multi_parts +=2;
-                    multi_parts +=2;
-                    //notify(InverterDevInform_All, iv);
+                    if(NULL != mCbPayload)
+                        (mCbPayload)(InverterDevInform_All, q->iv);
+                    q->iv->miMultiParts +=2;
+
                 } else {
                     DBGPRINTLN(F("3rd gen. inverter!"));
                 }
@@ -515,21 +535,24 @@ class Communication : public CommQueue<> {
                 //if(mSerialDebug) {
                     DPRINT(DBG_INFO,F("APPFW_MINVER "));
                     DBGPRINTLN(String((p->packet[10] << 8) + p->packet[11]));
-                    DPRINT(DBG_INFO,F("HWInfoAddr "));
+                    DBGPRINT(F("HWInfoAddr "));
                     DBGPRINTLN(String((p->packet[12] << 8) + p->packet[13]));
-                    DPRINT(DBG_INFO,F("PNInfoCRC_gusv "));
+                    DBGPRINT(F("PNInfoCRC_gusv "));
                     DBGPRINTLN(String((p->packet[14] << 8) + p->packet[15]));
                 //}
-                //mPayload[iv->id].multi_parts++;
-                multi_parts++;
+                if(NULL != mCbPayload)
+                    (mCbPayload)(InverterDevInform_Simple, q->iv);
+                q->iv->miMultiParts++;
             }
-            if(multi_parts > 5) {
+            if(q->iv->miMultiParts > 5) {
                 cmdDone(true);
                 mState = States::RESET;
                 q->iv->radioStatistics.rxSuccess++;
                 mHeu.setGotAll(q->iv);
+                q->iv->miMultiParts = 0;
             } else {
                 mHeu.setGotFragment(q->iv);
+                mState = States::WAIT;
             }
 
             /*if (mPayload[iv->id].multi_parts > 5) {
@@ -568,9 +591,8 @@ class Communication : public CommQueue<> {
 
             q->iv->setValue(q->iv->getPosByChFld(0, FLD_T, rec), rec, (float) ((int16_t)(p->packet[21] << 8) + p->packet[22])/10);
             q->iv->setValue(q->iv->getPosByChFld(0, FLD_IRR, rec), rec, (float) (calcIrradiation(q->iv, datachan)));
-            //mPayload[q->iv->id].rssi[(datachan-1)] = p->rssi;
 
-            if (datachan == 1) //mPayload[q->iv->id].rssi[(datachan-1)] = p->rssi;
+            if (datachan == 1)
                 q->iv->rssi = p->rssi;
             else if(q->iv->rssi > p->rssi)
                 q->iv->rssi = p->rssi;
@@ -597,6 +619,7 @@ class Communication : public CommQueue<> {
             } else if((p->packet[0] == (MI_REQ_CH1 + ALL_FRAMES)) && (q->iv->type == INV_TYPE_2CH)) {
                 //addImportant(q->iv, MI_REQ_CH2);
                 miNextRequest(MI_REQ_CH2, q);
+                //use also miMultiParts here for better statistics?
                 mHeu.setGotFragment(q->iv);
             } else {                                    // first data msg for 1ch, 2nd for 2ch
                 miComplete(q->iv);
@@ -604,25 +627,24 @@ class Communication : public CommQueue<> {
         }
 
         inline void miNextRequest(uint8_t cmd, const queue_s *q) {
-            //setAttempt();
+            incrAttempt();    // if function is called, we got something, and we necessarily need more transmissions for MI types...
             DPRINT_IVID(DBG_WARN, q->iv->id);
             DBGPRINT(F("next request ("));
             DBGPRINT(String(q->attempts));
             DBGPRINT(F(" attempts left): 0x"));
             DBGHEXLN(cmd);
 
-            if(q->attempts) {
+            //if(q->attempts) {
                 q->iv->radio->sendCmdPacket(q->iv, cmd, 0x00, true);
                 q->iv->radioStatistics.retransmits++;
                 mWaitTimeout = millis() + MI_TIMEOUT;
-                //chgCmd(Inverter<> *iv, uint8_t cmd, bool delOnPop = true)
                 chgCmd(cmd);
                 mState = States::WAIT;
-            } else {
+            /*} else {
                 add(q, true);
                 cmdDone();
                 mState = States::RESET;
-            }
+            }*/
         }
 
         inline void miStsConsolidate(const queue_s *q, uint8_t stschan,  record_t<> *rec, uint8_t uState, uint8_t uEnum, uint8_t lState = 0, uint8_t lEnum = 0) {
@@ -699,13 +721,10 @@ class Communication : public CommQueue<> {
 
 
         inline void miComplete(Inverter<> *iv) {
-            //if ( mPayload[iv->id].complete )
-            //    return; //if we got second message as well in repreated attempt
-            //mPayload[iv->id].complete = true;
-            //if (mSerialDebug) {
+            if (iv->radio->isSerialDebug()) {
                 DPRINT_IVID(DBG_INFO, iv->id);
                 DBGPRINTLN(F("got all data msgs"));
-            //}
+            }
             record_t<> *rec = iv->getRecordStruct(RealTimeRunData_Debug);
             iv->setValue(iv->getPosByChFld(0, FLD_YD, rec), rec, calcYieldDayCh0(iv,0));
 
@@ -751,7 +770,8 @@ class Communication : public CommQueue<> {
     private:
         States mState = States::RESET;
         uint32_t *mTimestamp;
-        uint32_t mWaitTimeout = 0;
+        uint32_t mWaitTimeout     = 0;
+        uint32_t mWaitTimeout_min = 0;
         std::array<frame_t, MAX_PAYLOAD_ENTRIES> mLocalBuf;
         bool mGotFragment = false;
         bool mFirstTry = false;
diff --git a/src/hm/Heuristic.h b/src/hm/Heuristic.h
index 7bf9f4a9..3ad249b9 100644
--- a/src/hm/Heuristic.h
+++ b/src/hm/Heuristic.h
@@ -62,7 +62,7 @@ class Heuristic {
 
         void printStatus(Inverter<> *iv) {
             DPRINT_IVID(DBG_INFO, iv->id);
-            DBGPRINT(F("CH qualities:"));
+            DBGPRINT(F("Radio infos:"));
             for(uint8_t i = 0; i < RF_MAX_CHANNEL_ID; i++) {
                 DBGPRINT(F(" "));
                 DBGPRINT(String(iv->txRfQuality[i]));
@@ -74,7 +74,9 @@ class Heuristic {
             DBGPRINT(F(", f: "));
             DBGPRINT(String(iv->radioStatistics.rxFail));
             DBGPRINT(F(", n: "));
-            DBGPRINTLN(String(iv->radioStatistics.rxFailNoAnser));
+            DBGPRINT(String(iv->radioStatistics.rxFailNoAnser));
+            DBGPRINT(F(" | p: "));                                  // better debugging for helpers...
+            DBGPRINTLN(String(iv->config->powerLevel));
         }
 
         bool getTestModeEnabled(void) {
diff --git a/src/hm/hmInverter.h b/src/hm/hmInverter.h
index f3d149c4..88a19a1b 100644
--- a/src/hm/hmInverter.h
+++ b/src/hm/hmInverter.h
@@ -125,6 +125,8 @@ class Inverter {
         uint16_t      alarmCnt;          // counts the total number of occurred alarms
         uint16_t      alarmLastId;       // lastId which was received
         int8_t        rssi;              // RSSI
+        uint8_t       miMultiParts;      // helper info for MI multiframe msgs
+        bool          mGotLastMsg;       // shows if inverter has already finished transmission cycle
         Radio         *radio;            // pointer to associated radio class
         statistics_t  radioStatistics;   // information about transmitted, failed, ... packets
         int8_t        txRfQuality[5];    // heuristics tx quality (check 'Heuristics.h')
@@ -150,8 +152,11 @@ class Inverter {
             alarmCnt           = 0;
             alarmLastId        = 0;
             rssi               = -127;
+            miMultiParts       = 0;
+            mGotLastMsg        = false;
             radio              = NULL;
             commEnabled        = true;
+
             memset(&radioStatistics, 0, sizeof(statistics_t));
             memset(txRfQuality, -6, 5);
 
diff --git a/src/hm/hmRadio.h b/src/hm/hmRadio.h
index a55c7d3c..a51504df 100644
--- a/src/hm/hmRadio.h
+++ b/src/hm/hmRadio.h
@@ -257,12 +257,14 @@ class HmRadio : public Radio {
                             isLastPackage = (p.packet[9] > ALL_FRAMES); // > ALL_FRAMES indicates last packet received
                         else if (p.packet[0] == ( 0x0f + ALL_FRAMES) )  // response from MI get information command
                             isLastPackage = (p.packet[9] > 0x10);       // > 0x10 indicates last packet received
-                        else if ((p.packet[0] != 0x88) && (p.packet[0] != 0x92)) // ignore fragment number zero and MI status messages //#0 was p.packet[0] != 0x00 &&
+                        else if ((p.packet[0] != 0x88) && (p.packet[0] != 0x92)) // ignore MI status messages //#0 was p.packet[0] != 0x00 &&
                             isLastPackage = true;                       // response from dev control command
                     }
                 }
                 yield();
             }
+            if(isLastPackage)
+                mLastIv->mGotLastMsg = true;
             return isLastPackage;
         }
 
@@ -280,7 +282,7 @@ class HmRadio : public Radio {
                 DBGPRINT(" CH");
                 DBGPRINT(String(mTxChIdx));
                 DBGPRINT(F(" | "));
-                ah::dumpBuf(mTxBuf, len);
+                ah::dumpBuf(mTxBuf, len, 1, 4, "#"+String(iv->id));
             }
 
             mNrf24.stopListening();
@@ -304,6 +306,7 @@ class HmRadio : public Radio {
         uint8_t mRfChLst[RF_CHANNELS] = {03, 23, 40, 61, 75}; // channel List:2403, 2423, 2440, 2461, 2475MHz
         uint8_t mTxChIdx = 0;
         uint8_t mRxChIdx = 0;
+        bool    mGotLastMsg = false;
         uint32_t mMillis;
 
         SPIClass* mSpi;
diff --git a/src/hm/radio.h b/src/hm/radio.h
index 07317e8c..e4beb071 100644
--- a/src/hm/radio.h
+++ b/src/hm/radio.h
@@ -38,6 +38,10 @@ class Radio {
             mSerialDebug = true;
         }
 
+        bool isSerialDebug() {
+            return mSerialDebug;
+        }
+
         void sendCmdPacket(Inverter<> *iv, uint8_t mid, uint8_t pid, bool isRetransmit, bool appendCrc16=true) {
             initPacket(getIvId(iv), mid, pid);
             sendPacket(iv, 10, isRetransmit, appendCrc16);
diff --git a/src/utils/helper.cpp b/src/utils/helper.cpp
index 4050c999..c7aefc1c 100644
--- a/src/utils/helper.cpp
+++ b/src/utils/helper.cpp
@@ -86,9 +86,12 @@ namespace ah {
         return ret;
     }
 
-    void dumpBuf(uint8_t buf[], uint8_t len) {
+    void dumpBuf(uint8_t buf[], uint8_t len, uint8_t firstRepl, uint8_t lastRepl, String repl) {
         for(uint8_t i = 0; i < len; i++) {
-            DHEX(buf[i]);
+            if(i < firstRepl || i > lastRepl)
+                DHEX(buf[i]);
+            else
+                DBGPRINT(repl);
             DBGPRINT(" ");
         }
         DBGPRINTLN("");
diff --git a/src/utils/helper.h b/src/utils/helper.h
index 252ca9fe..296729db 100644
--- a/src/utils/helper.h
+++ b/src/utils/helper.h
@@ -45,7 +45,7 @@ namespace ah {
     String getDateTimeStrFile(time_t t);
     String getTimeStr(time_t t);
     uint64_t Serial2u64(const char *val);
-    void dumpBuf(uint8_t buf[], uint8_t len);
+    void dumpBuf(uint8_t buf[], uint8_t len, uint8_t firstRepl = 0, uint8_t lastRepl = 0, String repl = "");
 }
 
 #endif /*__HELPER_H__*/