Are you using the Kensington FM digital transmitter/charger? We got one for Christmas and it seems to work just great. This one does connect through the dock on the ipod, and then to the cigarette lighter/whatever. I've not noticed any difficulties with sound -- in fact, we've been very, very pleased with the quality. (But I'm not a hard rock/pound out the base person, either. So that may be coloring my experience!)