high-pitch whine on AM stations

[CorvallisBMW]

I get the wierdest whine on all my AM stations, whether the ingition is on or off. It starts low and slowly increases in pitch until it's beyond audible range, then will drop back down if I wait a while or switch bands/turn it off then back on. Then it just repeats. Any idea what could cause this? fyi it's an aftermarket Sony deck.

[CorvallisBMW]

Anyone? any ideas?

[NomadE30]

No idea, my suggestion get a deck that is iPod ready

[StereoInstaller1]

Sports fan, huh?

Borrow a different deck from someone else, see if the issue remains. Likely an oscillation in the AM tuner.