Which program are you using to play the CD's with?
Xine, MPlayer (from the command line)
I also tried installing VLC from Slackware repo, but that didn't work at all. I did not troubleshoot this.
And how does it go when you rip CDs?
Perfectly, although I felt ripping was a bit slow. But then, ripping _is_ a bit slow. I could also play mp3's from USB stick, even though she has an USB 1.0 port. Audacious worked to, playing a list of mp3's.
Also, the drive seemed to access CD-ROMS just fine.
I was contemplating maybe a buffer problem, but I really venture outside my field of knowledge

But I felt the effect was comparable to streaming video when the site's upload is poor, or there's a bottleneck along the way. Ehm...everyone who watches very recent blockbuster movies from a Japanese site knows this effect

... at least, that is what it reminded me off. it looked like it wasn't building a buffer. But as I said, I have no idea if audioCD's work like that. The same programs on my machine play CD's perfectly well.