vdr crasht beim Beenden - was bedeutet der backtrace?

--- device.c    2017/05/30 11:06:11     4.23
+++ device.c    2018/01/27 14:45:08     4.26
@@ -120,6 +120,7 @@
   delete dvbSubtitleConverter;
   if (this == primaryDevice)
      primaryDevice = NULL;
+  Cancel(3);
 }

 bool cDevice::WaitForAllDevicesReady(int Timeout)
@@ -1673,6 +1674,7 @@
                  int Pid = TsPid(b);
                  bool IsScrambled = TsIsScrambled(b);
                  for (int i = 0; i < MAXRECEIVERS; i++) {
+                     cMutexLock MutexLock(&mutexReceiver);
                      cReceiver *Receiver = receiver[i];
                      if (Receiver && Receiver->WantsPid(Pid)) {
                         Receiver->Receive(b, TS_SIZE);
@@ -1768,10 +1770,8 @@
                 }
              }
          Receiver->Activate(true);
-         Lock();
          Receiver->device = this;
          receiver[i] = Receiver;
-         Unlock();
          if (camSlot && Receiver->priority > MINPRIORITY) { // priority check to avoid an infinite loop with the CAM slot's caPidReceiver
             camSlot->StartDecrypting();
             if (camSlot->WantsTsData()) {
@@ -1801,13 +1801,11 @@
   if (!Receiver || Receiver->device != this)
      return;
   bool receiversLeft = false;
-  cMutexLock MutexLock(&mutexReceiver);
+  mutexReceiver.Lock();
   for (int i = 0; i < MAXRECEIVERS; i++) {
       if (receiver[i] == Receiver) {
-         Lock();
          receiver[i] = NULL;
          Receiver->device = NULL;
-         Unlock();
          Receiver->Activate(false);
          for (int n = 0; n < Receiver->numPids; n++)
              DelPid(Receiver->pids[n]);
@@ -1815,6 +1813,7 @@
       else if (receiver[i])
          receiversLeft = true;
       }
+  mutexReceiver.Unlock();
   if (camSlot) {
      if (Receiver->priority > MINPRIORITY) { // priority check to avoid an infinite loop with the CAM slot's caPidReceiver
         camSlot->StartDecrypting();