That's odd. It seems to me there's clock problem. Were you 44.1 or 48k? Obviously you would set the control panel to clock to the incoming lightpipe normally but if it's misbehaving, it's not seeing the clock. I'd check to see what the HD sampling rate is set at and confirm the MOTU is set the same. As an experiment try setting the MOTU clock to internal to see if Media Player works. Failing all that I'd pull the MOTU PCI card, unistall the MOTU software and re-install it, THEN put the PCI card back in, in that order