I think are the frequencies used. I don't have any experience with the Rosen players, but are you sure its supposed to come through the speakers?
As they normaly come with 2x headphones, and speakers are an option extra. I take it you have checked in all pockets under front seats and under rear floor and under center floor for any hidden.
Quote Touran Forum: I seem to remember some very early threads about the Rosens and I'm sure
VW UK were saying you couldn't have it coming through the speakers.
Pretty sure you could get some kind of interface off eBay though.
The Rosen A7 should have a built in FM modulator/transmitter... it sends
sound on the FM band. It can be tuned in on the radio in the car, and
thus you hear sound from the Rosen on your car speakers (
Description
).
Here is the link to the A7 Manual;
Rosen A7 Owner's Manual
.
Hope helps.