My modulator has 3 frequency outputs all around the 88-89mhz mark. This is
OK (and the unit needs to be switchable or you'll get interference on
other frequencies) but certain areas of the county use these frequencies
for Radio 2 and if you drive into an area with a very strong signal, it
will drown out the mp3 signal and there's nothing you can do but grin and
bear it, or stop the car and manually change the output frequency.


Thanks for that . I was thinking of wiring up a changeover switch between
either car aerial or FM modulator output. Then the frequency shouldn't
matter and I should get best reception either way.

Unless of course someone tells me this wont work!