The Ots Labs CD-DA subsystem is what enables you to play audio CDs directly in the CD Scratch turntables. The CD tracks are played digitally, as opposed to the analog method, which means that they go through the superior Ots Labs audio pipeline.
You can apply pitch/tempo adjustments to your CD tracks, just as if they were a digital audio file. In short, these tracks are treated just like a file. They even mix correctly. You can even play or mix between two tracks from the same CD at the same time.
How well or not the Ots Labs CD-DA subsystem works on your computer will depend on the quality of your CD-ROM drive(s). For details on the Ots Labs CD-DA subsystem requirements here.
To find out about the Ots Labs CD-DA cache system click here.
Ots Labs CD-DA requirements
CD-DA cache system
How to play an audio CD