Hi,
I've just received my playdate, and I finally managed to investigate the problem.
It looks like the (on device only) silent crash comes from the setRate method of the audio player.
In my app i use the crank to compute the audio rate, and at the start of the app, when the crank is goint out of the slot, some very small variations are generated, producing this problem.
More info here: Sampleplayer silent crash using setRate