API to use for high-level audio playback to a specific audio device?

I'm working on a little light and sound controller in Swift, driving DMX lights and audio.

For the audio portion, I need to play a bunch of looping sounds (long-duration MP3s), and occasionally play sound effects (short-duration sounds, varying formats). I want all of this mixed into selected channels on specific devices. That is, I might have one audio stream going to the left channel, and a completely different one going to the right channel.

What's the right API to do this from Swift? Core Audio? AVPlayer stuff?

API to use for high-level audio playback to a specific audio device?
 
 
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