yellowRX

Today my stereo was working fine, but for somereason later on in the day it would not go to CD mode or EX mode. I want to take it into the dealer but i'm scared they will blame it on my aftermarket stereo, I also have the Aux out audio link for the Ipod. Dose anyone know what might have happen to it? What should I do, should I take it into the dealer? If they blame me do they have the right to, and is it my fault? the HU works fine for raido and has no problem with the AM FM. but the CD and EX mode wont show up, it just disappeared.