I am trying to set my project to 44.1khz in Project Settings->Platforms - Mac->Audio Mixer Sample Rate and have it set to 44100. However upon loading the engine, Audio MIDI Setup shows my audio device switches to 48k. If I manually set it back to 44.1, and Play In-Engine, it gets set back to 48k. I don’t seem to see any way around it. I am using the new audio engine on macOS, so maybe the bug lies with that?
Also, if you look through the source, there’s a lot of assumptions about sample rate.
A few examples:
// poor man's re-sampling const float ResampleRatio = (float)SinkSampleRate / 44100.0f;
return (double)VoiceState.SamplesPlayed / 44100;
float FilterConstant = 2.0f * FMath::Sin(PI * 6000.0f * InteriorLPF / 48000);