I hate to say it, but I think you're hallucinating. You'll need to have a patch cord from the CDRW to your mac audio input port in order to hear audio on the mac.
Check the Sound Control panel's Sound In panel to see if your CDRW is there. If it is, select it and I apologize. If it's not, then you'll have to connect a patch cord and select Mic in in order to hear audio.