Added audio output via USB.

Small fixes.

MicroDexed.ino

@@ -54,6 +54,9 @@ AudioAnalyzePeak         peak1;
 AudioEffectDelay         delay1;
 AudioMixer4              mixer1;
 AudioMixer4              mixer2;
+AudioAmplifier           volume_r;
+AudioAmplifier           volume_l;
+AudioOutputUSB           usb1;
 AudioConnection          patchCord0(queue1, peak1);
 AudioConnection          patchCord1(queue1, 0, mixer1, 0);
 AudioConnection          patchCord2(queue1, 0, mixer2, 0);
@@ -61,24 +64,24 @@ AudioConnection          patchCord3(delay1, 0, mixer1, 1);
 AudioConnection          patchCord4(delay1, 0, mixer2, 2);
 AudioConnection          patchCord5(mixer1, delay1);
 AudioConnection          patchCord6(mixer1, 0, mixer2, 1);
-AudioAmplifier           volume_r;
-AudioAmplifier           volume_l;
 AudioConnection          patchCord7(mixer2, volume_r);
 AudioConnection          patchCord8(mixer2, volume_l);
+AudioConnection          patchCord9(mixer2, 0, usb1, 0);
+AudioConnection          patchCord10(mixer2, 0, usb1, 1);
 #if defined(TEENSY_AUDIO_BOARD)
 AudioOutputI2S           i2s1;
-AudioConnection          patchCord9(volume_r, 0, i2s1, 0);
-AudioConnection          patchCord10(volume_l, 0, i2s1, 1);
+AudioConnection          patchCord11(volume_r, 0, i2s1, 0);
+AudioConnection          patchCord12(volume_l, 0, i2s1, 1);
 AudioControlSGTL5000     sgtl5000_1;
 #elif defined(TGA_AUDIO_BOARD)
 AudioOutputI2S           i2s1;
-AudioConnection          patchCord9(volume_r, 0, i2s1, 0);
-AudioConnection          patchCord10(volume_l, 0, i2s1, 1);
+AudioConnection          patchCord11(volume_r, 0, i2s1, 0);
+AudioConnection          patchCord12(volume_l, 0, i2s1, 1);
 AudioControlWM8731master wm8731_1;
 #else
 AudioOutputPT8211        pt8211_1;
-AudioConnection          patchCord9(volume_r, 0, pt8211_1, 0);
-AudioConnection          patchCord10(volume_l, 0, pt8211_1, 1);
+AudioConnection          patchCord11(volume_r, 0, pt8211_1, 0);
+AudioConnection          patchCord12(volume_l, 0, pt8211_1, 1);
 #endif
 
 Dexed* dexed = new Dexed(SAMPLE_RATE);