Stick some headphones in, and see if you get the same distortion. If you do, it's your soundcard.

I should have done that anyway. Yeah, the distortion is still there. Do you agree that 207 kbps mp3 should be high enough quality to avoid this kind of thing?

So the sound card! all along..

It could still be the mp3, even at a high bit rate. You're experiencing a phenomenon known as "clipping," which tends cause the sound to distort or cut out at high volumes and pitches. You can get rid of at least some of the clipping by reducing the volume of the files with MP3Gain.

Was it recorded live? If so, the problem may be on the recording end. Otherwise, yeah, cut the gain.

ditto it likely being a problem with recording. if it's clipping with headphones your ears would probably be bleeding (assuming you normally don't need to have the volume turned way up).

if you have a program that will plot out the waveform (no idea what) you should be able to identify the loud bits (biggest wiggles - this is a technical term). if the tops of the biggest wiggles are all cut off flat (another technical term) then the problem is in the recording.

hmm. although high notes even at low volume is kind of odd. i don't have an explanation for that if you really hear it through speakers and headphones.

Hmmm. I have noticed it on a variety of my music, but my mp3s are a mixed bag, and I probably have a lot of cruddy ones in any case.

I'm going to try the AV-710 sound card. It's only $23.

I've been meaning to upgrade my sound card anyhow, and I'll be interested to see if I notice any difference in general.

I can't recommend the Turtle Beach Riveria enough. I lucked out when I got that at Fry's for 29.99. Full duplex real 6-channel audio (5.1), with a nearly pro-level signal to noise ratio. (96-98 dB or something like that.) The channels are fully assignable for doing things like quadraphonic sound, or dolby or STS surround, or multi-channel audio applications like recording while playing back, etc. It also has an optical output for use with pro audio toys or home theaters or the like.

If other MP3s don't do what you're talking about consistantly, it's probably that particular MP3.