Default Mixerchannel rate to upstream default on creation.

Author: finneyj

inc/Mixer2.h

@@ -165,7 +165,7 @@ class Mixer2 : public DataSource
      * @param sampleRate (samples per second) - if set to zero, defaults to the output sample rate of the Mixer
      * @param sampleRange (quantization levels) the difference between the maximum and minimum sample level on the input channel
      */
-    MixerChannel *addChannel(DataSource &stream, float sampleRate = CONFIG_MIXER_DEFAULT_CHANNEL_SAMPLERATE, int sampleRange = CONFIG_MIXER_INTERNAL_RANGE);
+    MixerChannel *addChannel(DataSource &stream, float sampleRate = 0.0f, int sampleRange = CONFIG_MIXER_INTERNAL_RANGE);
 
     /**
      * Removes a channel from the mixer

source/MicroBitAudio.cpp

@@ -61,7 +61,7 @@ MicroBitAudio::MicroBitAudio(NRF52Pin &pin, NRF52Pin &speaker, NRF52ADC &adc, NR
     synth.allowEmptyBuffers(true);
 
     mic = adc.getChannel(microphone, false);
-    adc.setSamplePeriod( 1e6 / 11000 );
+    mic->setSampleRate(11000);
     mic->setGain(7, 0);
 
     activateMic();

source/Mixer2.cpp

@@ -94,7 +94,7 @@ MixerChannel *Mixer2::addChannel(DataSource &stream, float sampleRate, int sampl
     MixerChannel *c = new MixerChannel();
     c->stream = &stream;
     c->range = sampleRange;
-    c->rate = sampleRate ? sampleRate : outputRate;
+    c->rate = sampleRate ? sampleRate : stream.getSampleRate();
     c->pullRequests = 0;
     c->in = NULL;
     c->end = NULL;