Meta Spark Studio supports mono M4A files.
Use files with a 44.1kHz sample rate and 16-bit-depth resolution, to make the size of the effect as small as possible but preserve quality. You can do this through a digital audio workstation (DAW) or a program like iTunes.
Audio clips should be prepped. If you're converting ambient or music beds from stereo tracks to mono, convert to summed mono rather than dropping one of the tracks - to avoid losing elements of the audio file. Convert files to the lowest kbps possible, while maintaining your desired degree of audio quality. Test clips through your device to check the quality is correct. We don't recommend going lower than 64kbps when converting to m4as.
To import an audio clip, go to the Assets panel:
For one-shot audio effects triggered by pulses or to add effects like distortion and pitch shifting, use the Audio Player and Single or Multi-Clip Controller patches.
For looping audio, connect an an audio playback controller. An audio playback controller can also be configured to play, stop and restart audio in response to boolean signals.