playback is stuttering. None of the controls seem to have any effect.

This can be a symptom of the player running out of memory. v3alpha3 uses a lot more
memory than its predecessors. On my 12MB mk2 player, v3alpha3 runs out of
memory simply by having more than 7000 tunes in the database. The stuttering
you describe are accompanied by lots of VM messages on the serial port.

I had to reduce the tune cache to make v3alpha3 work for me.

IIRC, Ogg tunes can demand extrordaniry resources from the decoder,
making your player run out of memory.

Pim