depends on the encoding.
from motorola:
PLAYABLE FORMATS
AAC, H.263, H.264, MP3, MPEG-4, WAV, eAAC+, WMA v10, WMA v9, MIDI, AAC+
there are apps you can download that will play other formats, however, i don't remember very many of them being that great. someone else will have to chime in on app suggestions. did coreplayer ever release their player?
