I recently installed an Alpine 9830 headunit into my car. Generally if I listen to the radio I listen to talk AM radio. However, I've noticed that now I've installed this new head unit AM radio has an awful sound behind it. The sound is a loud pitch squeal that changes when the AC is turned on or if a turn signal is used. The sound stops though if the engine is turned off.
Any ideas as to why this is happening? I've installed it into a 2003 Mitsubishi Lancer.
It might just be part of the Alpine deck. They have a disreputable reputation for their AM tuners. You might possibly try making sure the connection to the antenna is secure, though I'm sure you've already done so.
Alpines have bad AM reception but i mean come on...AM radio wtf...i radio doesnt even work in my car(need to buy an antenna adaptor) and im not missing it at all but that might be my area...radio sucks in charlotte