I2SStream: initialize mute pin

Author: pschatzmann

src/AudioTools/CoreAudio/AudioI2S/I2SStream.h

@@ -34,7 +34,7 @@ class I2SStream : public AudioStream {
  public:
   I2SStream() = default;
   ~I2SStream() { end(); }
-  
+
 #ifdef ARDUINO
   I2SStream(int mute_pin) {
     TRACED();
@@ -83,10 +83,12 @@ class I2SStream : public AudioStream {
 
   /// Stops the I2S interface
   void end() {
-    TRACEI();
-    is_active = false;
-    mute(true);
-    i2s.end();
+    if (is_active) {
+      TRACEI();
+      is_active = false;
+      mute(true);
+      i2s.end();
+    }
   }
 
   /// updates the sample rate dynamically
@@ -143,7 +145,7 @@ class I2SStream : public AudioStream {
 
  protected:
   I2SDriver i2s;
-  int mute_pin;
+  int mute_pin = -1;
   bool is_active = false;
 
   /// set mute pin on or off