Just mounted one of my older HDD after some repairs (a contact) with 512 kB buffer, IIRC it's PIO4. Same file played from a 8 MB ATA 100 HDD works OK, but from this HDD, same effect, video hurry back to catch up with the sound. It's sure the transfer speed it's low. Maybe this could be an explanation. What HDD do you have and do you have ATA drivers installed correctly ? It's just an ideea.