I pod not working through interface. Phone volume decreasing.
 

I started having problems with my I- pod not playing songs I selected, and also only playing a few in playlist, then stopping. Now I- pod shows up on screen, but does not play. Phone volume while talking also is decreasing. Do I need a new interface cord for I- pod? I- pod otherwise works fine.Everything has worked fine for past 3 years.2008 G35X-S.