Stereo & Electronics - How do I change CD's with my 12 disc changer?

I have a 98 Z with the stock changer and monsoon cd player, I am trying to figure out how to switch the cd's using the deck. Ive tried hitting cd/aux and its only reading disc 8. The cd's are turned correctly and installed right. Please help me thanks

Radio preset button 5. :)

Ok thank you so much, my car didnt have the owners manual and I couldnt find anything online.

4th Generation Owners Manuals (http://www.camarohighway.com/Manuals/index.htm)