Master/Slave doesn't really matter. Plug the audio cable into whichever drive you plan on listening to audio CDs from. Back to the first question. Your best bet is to have the CD devices on two separate channels. I don't know what you have on IDE 1, but I would probably put the CD-ROM as slave on IDE 1 and put the burner as master on IDE 2 this leaves slave on IDE 2 open for whatever you have as slave on IDE 1 right now. The reason for this change is so that you have maximum bandwidth available for burning from CD-ROM or hard drive. If I were loading new software from a CD in this configuration, I would probably use the burner to do it to increase the data transfer speed.