message: fix crash in sound mixer
diff: @@ -35,7 +35,6 @@ void Mixer::setMusic(const Music& m,DMUS_EMBELLISHT_TYPES e) {
  return;
  nextMus = m.impl;
  - patEnd = sampleCursor;
  embellishment.store(e);
  //current = m.impl;
  //grooveCounter.store(0);
  @@ -285,7 +284,7 @@ void Mixer::mix(int16_t *out, size_t samples) {
  out += stp.samples*2;
  samplesRemain-= size_t(stp.samples);
  - if(sampleCursor==patEnd) {
  + if(sampleCursor==patEnd || nextMus!=nullptr) {
  nextPattern();
  }
  }
  