When I plug my ipod touch into my car using an aux cable I hear an underlying hissing/squealing noise. It's sort of like the noise you hear when people in old movies are trying to fiddle with radio dials to get a clear signal. Here is what is confusing me. 1. When I plug another mp3 player into my car instead of the ipod it's totally clear. 2. When I plug my ipod into headphones or speakers its totally clear again. I'm not sure where the problem lies. If it was a problem w/ my aux cable I'd think i'd hear the same problem when I plugged in the other mp3 player. Any thoughts?