diff --git a/Aux/Makefile b/Aux/Makefile
index c025106..f87921e 100644
--- a/Aux/Makefile
+++ b/Aux/Makefile
@@ -6,7 +6,7 @@
 CC	=	g++
 
 #COPTS	=	-fPIC -DLINUX -O2 -std=c++17 -lpthread
-COPTS	=	-fPIC -DLINUX -g -O2 -Wall -std=c++17 -lpthread
+COPTS	=	-fPIC -DLINUX -g -O0 -Wall -std=c++17 -lpthread
 
 CAENLIBS	=	-lCAENDigitizer
 
diff --git a/Aux/fsuReader.h b/Aux/fsuReader.h
index 42277a3..7a3cabb 100644
--- a/Aux/fsuReader.h
+++ b/Aux/fsuReader.h
@@ -1,4 +1,4 @@
-#include "ClassData.h"
+#include "../ClassData.h"
 
 class FSUReader{
 
diff --git a/Aux/test.cpp b/Aux/test.cpp
index 7e8ebc4..18b3b6b 100644
--- a/Aux/test.cpp
+++ b/Aux/test.cpp
@@ -75,7 +75,8 @@ int main(int argc, char* argv[]){
     
     data->PrintAllData(true);
 
-    builder->BuildEvents(false, true, true);
+    //builder->BuildEvents(false, true, true);
+    builder->BuildEventsBackWard(20, true);
 
     builder->PrintStat();
     // int index = data->NumEventsDecoded[0];
@@ -86,7 +87,7 @@ int main(int argc, char* argv[]){
 
   //data->CloseSaveFile();
   builder->BuildEvents(true, true, true);
-  
+
   data->PrintAllData();
 
   builder->PrintAllEvent(); // TODO
diff --git a/MultiBuilder.cpp b/MultiBuilder.cpp
index 5527895..750bb91 100644
--- a/MultiBuilder.cpp
+++ b/MultiBuilder.cpp
@@ -281,7 +281,7 @@ void MultiBuilder::BuildEventsBackWard(int maxNumEvent, bool verbose){
 
   // remember the end of DataIndex, prevent over build
   for( int k = 0; k < nData; k++){
-    for( int i = 0; i < data[i]->GetNChannel(); i++){
+    for( int i = 0; i < data[k]->GetNChannel(); i++){
       nextIndex[k][i] = data[k]->DataIndex[i];
       loopIndex[k][i] = data[k]->LoopIndex[i];
     }
@@ -363,7 +363,7 @@ void MultiBuilder::BuildEventsBackWard(int maxNumEvent, bool verbose){
 
     }
 
-  }while(nExhaushedCh < nData * MaxNChannels && eventBuilt <= maxNumEvent);
+  }while(nExhaushedCh < nData * MaxNChannels && eventBuilt < maxNumEvent);
 
   // // remember the end of DataIndex, prevent over build
   // for( int k = 0; k < nData; k++){