diff --git a/soundcube-firmware/ringbuffer.h b/soundcube-firmware/ringbuffer.h
index b80bfa5..c3f5339 100644
--- a/soundcube-firmware/ringbuffer.h
+++ b/soundcube-firmware/ringbuffer.h
@@ -6,11 +6,11 @@ class RingBuffer{
     RingBuffer() {}
     RingBuffer(size_t size) : bufferSize(size) {}
 
-  void setSize(size_t size) {
-    bufferSize = size;
-  }
+    void setSize(size_t size) {
+      bufferSize = size;
+    }
 
-	void begin(){
+    void begin(){
       buffer = new T[bufferSize];
     }
 
diff --git a/soundcube-firmware/soundcube-firmware.ino b/soundcube-firmware/soundcube-firmware.ino
index a7b1ee7..431a94a 100644
--- a/soundcube-firmware/soundcube-firmware.ino
+++ b/soundcube-firmware/soundcube-firmware.ino
@@ -97,12 +97,13 @@ size_t tape_write = 0;
 
 void codec_transmit() {
   for(int i = 0; i < count; i++){
-    int16_t sample = 0;
     int j = active % NSTREAMS;
-    sample = stream[j].get();
-    buffer[i] = sample >> 2;
+    for(int k = 0; k < NSTREAMS; k++){
+      int16_t sample = 0;
+      sample = stream[k].get();
+      buffer[i] += sample >> 2;
+    }
   }
-  
   i2s.write((const uint8_t *)&buffer, count * sizeof(int16_t));
 }
 
@@ -269,7 +270,7 @@ void setup() {
           Serial.print(stream[i].wavefile.blockalign);
           Serial.println(" bytes");
 
-          stream[i].play();
+          //stream[i].play();
           stream[i].wavefile.loop = true;
         } else {
           Serial.println("file loading error");
@@ -370,6 +371,7 @@ void loop() {
       Serial.println("vol down");
       codec.volumeDown();
     }
+
     if(buttons[CVOUTL]) {
       Serial.println("vol up");
       codec.volumeUp();
@@ -386,21 +388,26 @@ void loop() {
       dac.setValue(1, !dactest ? 0 : 65535);
     }
 
+    if(buttons[SELECT]){
+      stream[active % NSTREAMS].toggle();
+    }
+
     Serial.println(codec.getVolumeL());
 
-    for(int i = 0; i < NSTREAMS; i++){
-      stream[i].pause();  
-    }
-    stream[active % NSTREAMS].play();
+    //for(int i = 0; i < NSTREAMS; i++){
+    //  stream[i].pause();  
+   // }
+    //stream[active % NSTREAMS].play();
 
     buttonChanged = false;
   }
 
-  //ac.setValue(0, dactest ? 0 : sin((float)millis() / 100.0f) * 32768 + 32768);
+  //dac.setValue(0, dactest ? 0 : sin((float)millis() / 100.0f) * 32768 + 32768);
 
   // empty LED matrix
   for (int i = 0; i < 13; i++) {
     ui_leds[lut_matrix[i]] = CRGB(0, 0, 0);
+    if(stream[i % NSTREAMS].isPlaying()) ui_leds[lut_matrix[i % NSTREAMS]] = CRGB(0, 50, 0);
   }
   
   // set active LED matrix LED
@@ -426,22 +433,4 @@ void loop() {
 
   //delay(20); // wait 1ms
 
-}
-
-void setup1(){
-  // while(1){
-  //   if(streams_loaded){
-  //     int16_t l, r;
-  //     i2s.read16(&l, &r);
-
-  //     int j = active % NSTREAMS;
-  //     l = stream[j].get() >> 2;
-  //     r = stream[j].get() >> 2;
-
-  //     i2s.write16(l, r);
-  //   }
-  // }  
-}
-
-void loop1(){
 }
\ No newline at end of file
diff --git a/soundcube-firmware/wavestream.h b/soundcube-firmware/wavestream.h
index f42d01d..db79420 100644
--- a/soundcube-firmware/wavestream.h
+++ b/soundcube-firmware/wavestream.h
@@ -119,6 +119,8 @@ class WaveStream{
       return true;
     }
 
+    void toggle(){playing = !playing;}
+
     void play(){playing = true;}
 
     void stop(){
@@ -142,6 +144,10 @@ class WaveStream{
       return playing ? wavefile.get() : 0;
     }
 
+    bool isPlaying(){
+      return playing;
+    }
+
   //private:
 
     WaveFile wavefile;