diff --git a/common/JackCallbackNetIOAdapter.cpp b/common/JackCallbackNetIOAdapter.cpp
index 4af008f0..edd39fcd 100644
--- a/common/JackCallbackNetIOAdapter.cpp
+++ b/common/JackCallbackNetIOAdapter.cpp
@@ -94,6 +94,8 @@ JackCallbackNetIOAdapter::JackCallbackNetIOAdapter(jack_client_t* jack_client,
 {
     int i;
     
+    printf("input , %ld  %ld\n", input, output);
+    
     fCaptureRingBuffer = new JackResampler*[fCaptureChannels];
     fPlaybackRingBuffer = new JackResampler*[fPlaybackChannels];
     
diff --git a/common/JackNetIOAdapter.cpp b/common/JackNetIOAdapter.cpp
index 54cb5f0c..ad21bd66 100644
--- a/common/JackNetIOAdapter.cpp
+++ b/common/JackNetIOAdapter.cpp
@@ -119,6 +119,9 @@ extern "C"
 #include "JackPortAudioIOAdapter.h"
 #endif
 
+#define max(x,y) (((x)>(y)) ? (x) : (y))
+#define min(x,y) (((x)<(y)) ? (x) : (y))
+
 	EXPORT int jack_initialize(jack_client_t* jack_client, const char* load_init)
 	{
 		if (adapter) {
@@ -142,7 +145,10 @@ extern "C"
             }
             if (ports)
                 free(ports);
-
+                
+            input = max(2, input);
+            output = max(2, output);
+         
         #ifdef __linux__
             adapter = new Jack::JackCallbackNetIOAdapter(jack_client, 
                 new Jack::JackAlsaIOAdapter(input, output, jack_get_buffer_size(jack_client), jack_get_sample_rate(jack_client)), input, output);