Lossless files contain errors

I use my Window Vista Ultimate PC to rip CDs to lossless files using error correction. I just have an ordinary CDR drive and a mid+ level NVidia card.

I play the files through my iPod Classic 160-gig, into a Wadia 170i and via coax out into my Playback Designs MPS-5's DAC. Most files sound like the original CDs when played through the iPod/Wadia/PD combo, but a few sound seriously "off" with the vocal and instrumental timbres changing slightly.

When I re-ripped a few of the offending the files, the new files could not be distinguished from the original CDs. What gives? Is there a way to get an error correction report at the end of a rip? (I'm just using the latest version of iTunes for the rips).

I'm convinced that something occasionally goes wrong in the error correction process. I've aborted one or two rips because the process was going slower than real time. When I restarted the rip everything was ok. Now, with my new experience replacing files for the better, I'm wondering if error correction sometimes elects a "good enough" attitude and just gives you a crummy file.

Is there a way that I can be certain that my lossless files are "bit perfect?"

Dave