its not the CPU or the ROM, or the app and it won't be fixed in ICS. Its a artifact of the Advanced Audio Distribution Profile (A2DP) Bluetooth protocol. It buffers a couple of seconds of audio before it starts transmitting because when it was specd. they intended it only for music playback. Now it is pressed into service for video audio and there is no way to sync the playback. Perhaps more advanced players will arrive on the scene someday and allow for adjusting the timing. something like VLC maybe, but for now, you can't fix it.
Days of free media are almost over as the biggies look for more revenue streaming from your wallet... ...Don't believe me? Take a look at all the flagship models now being sold WITHOUT microSD card slots.