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I have developed in my '08 Mazda3 a most annoying buzz in the AM radio when I start the car up in the morning. I notice when I accelerate that it gets louder and when I let up on the accelerator it lets up too. I also hear it a little at idle. If you can give any suggestions, I'll be most appreciative. I only listen to AM radio and it was so nice not having any noise at all in this radio. When I took it to the dealer they did the usual diagnostics and couldn't replicate the noise...of course. I described the issue as maybe an EMI problem (my former husband was an engineer so I know a little about it) and they did not seem to understand what I was talking about.