Audio distortion (clipping) on computer drives/players but not dvd players

[Left/Right]

Hello all,
I work at a disc manufacturing company and i work in a testing department.
If it makes a difference, i do a good bit of audio engineering but am a bit of a noob at dvd authoring

Anyhow,
a client has turned in a previously molded disc as a new master at my company...
it clips (digital audio distortion) continuously at high audio signal levels on several computer drives (in nero showtime, wmp)

but not on any of the dvd players we have here for testing.

wonder if any of you have encountered this problem and if you know the reason for it.
i'm guessing its within authoring... possibly a dvd audio codec issue? or do dvds even data-compress audio? i'm unsure of how the authoring software functions...

thanks in advance.

[Left/Right]

also i'm 99% sure its not the computers or our systems volume/gain settings...
we do 100s of these discs daily and this is the first time we've gotten clipping on the computers but not on the dvd players.

[Soopafresh]

DVD audio is either WAV, MP2, or AC3 . Virtually all DVD players have the ability to play these file formats back. Not all PCs do. You have to install the correct codecs to do so.

Another interesting thing would be to demux one of the VOB files using DGindex and play the audio back alone