Buzzing in Bose speakers until warmed up

[skybolt31]

I have an 86 with the stock Bose system and I replaced one of the front speakers, just the paper speaker, not the amp and all was well for about a month. Now when I start the car, there will be a buzzing that seems to come from the rear speakers, and it is related to engine speed. It is not affected by the volume control and when I shut the radio off, it stops. It will do this for 3-4 minutes after the car starts and then is fine. Any ideas?

[RandyJ75]

Yes- the amps are going bad. this started in my 90 until it did not go away. But the new system sounds 150% better...

Good Luck

P.S. did you read the c4 sticky at the top? Lots of good info there.