Actually you don't have to mount audio CDs, you should just be able to open a CD player proggy and go. KsCD, or even command line workbone. Audio CDs work differently under linux, you don't actually read the data off the CD, instead you run an app that spins the CD up and opens the audio channels going to the soundcard from the CD drive.
Also make sure the cd audio channel on your sound card didn't get muted by linux. Either run kmixer from the menu or "run command..." "kmix" to start it or at the worst run rexima from command line and make sure that the CD channel isn't set at zero volume.