diff --git a/FSUDAQ.cpp b/FSUDAQ.cpp
index 3eb2d39..d58aacd 100644
--- a/FSUDAQ.cpp
+++ b/FSUDAQ.cpp
@@ -683,7 +683,7 @@ void MainWindow::OpenDigitizers(){
 
   canvas = new SingleSpectra(digi, nDigi, rawDataPath);
   histThread = new TimingThread(this);
-  histThread->SetWaitTimeinSec(0.5);
+  histThread->SetWaitTimeinSec(canvas->GetMaxFillTime()/1000.);
   connect(histThread, &TimingThread::timeUp, this, [=](){
     if( canvas == nullptr &&   !canvas->IsFillHistograms()) return; 
     canvas->FillHistograms();
diff --git a/SingleSpectra.cpp b/SingleSpectra.cpp
index fa62d8d..111edab 100644
--- a/SingleSpectra.cpp
+++ b/SingleSpectra.cpp
@@ -13,6 +13,8 @@ SingleSpectra::SingleSpectra(Digitizer ** digi, unsigned int nDigi, QString rawD
   this->nDigi = nDigi;
   this->rawDataPath = rawDataPath;
 
+  maxFillTimeinMilliSec = 500;
+
   isSignalSlotActive = true;
 
   setWindowTitle("1-D Histograms");
@@ -201,9 +203,13 @@ void SingleSpectra::ChangeHistView(){
 void SingleSpectra::FillHistograms(){
   if( !fillHistograms ) return;
 
+  unsigned short maxFillTimePerDigi = maxFillTimeinMilliSec/nDigi;
+  timespec t0, t1;
+
   for( int i = 0; i < nDigi; i++){
 
     digiMTX[i].lock();
+    clock_gettime(CLOCK_REALTIME, &t0);
     for( int ch = 0; ch < digi[i]->GetNumInputCh(); ch ++ ){
       int lastIndex = digi[i]->GetData()->GetDataIndex(ch);
       if( lastIndex < 0 ) continue;
@@ -233,6 +239,9 @@ void SingleSpectra::FillHistograms(){
       }
       if( histVisibility[i][ch]  ) hist[i][ch]->UpdatePlot();
       if( hist2DVisibility[i] ) hist2D[i]->UpdatePlot();
+
+      clock_gettime(CLOCK_REALTIME, &t1);
+      if( t1.tv_nsec - t0.tv_nsec + (t1.tv_sec - t0.tv_sec)*1e9 > maxFillTimePerDigi * 1e6 ) break;  
     }
     digiMTX[i].unlock();
 
diff --git a/SingleSpectra.h b/SingleSpectra.h
index 36d1ebb..a91794e 100644
--- a/SingleSpectra.h
+++ b/SingleSpectra.h
@@ -35,6 +35,9 @@ public:
   void LoadSetting();
   void SaveSetting();
 
+  void SetMaxFillTime(unsigned short milliSec) { maxFillTimeinMilliSec = milliSec;}
+  unsigned short GetMaxFillTime() const {return maxFillTimeinMilliSec;};
+
 public slots:
   void FillHistograms();
   void ChangeHistView();
@@ -66,6 +69,8 @@ private:
 
   QString rawDataPath;
 
+  unsigned short maxFillTimeinMilliSec;
+
   bool isSignalSlotActive;
 
 };