Audio Systems: Noise Bose premium radio 95 legend, radio 95, speaker units

Question
head unit:bose premium(oem)
ref #:cm6923
12v
frequency range: FM 87.75--107.9Mhz
frequency range: AM 530 Mhz--1710Khz

This problem started two years ago,the radio started to make a loud buzzing noise.The noise would come and go.I tried turning the volume all the way down, but the buzzing/sizzling noise continued.I would then turn the radio off until the next day. Sometimes there was no noise, but other time the noise would come back. I eventually sent the head unit to Willmans electronic to be fixed. I got it back it worked fine for two years. The problem has returned, it doesnt matter if i try to play the cd or radio i can hardly hear the radio through all that loud irritating noise. I don't know if something else is causing it to go bad such as the Amp. It cost a lot to fix the problem the last time. What could be the problem ,and could i fix the problem myself. If so what steps should i take
I have since removed the head unit and opened it up to se if any capacitor/resistor where damaged. Don't really Know what to look for
thanks
olwen

Answer
Hello Olwen,
The problem may not be with the stereo unit, but with the amplifiers that are mounted along with each speaker. Just to be on the safe side try removing any of the speaker units to see if an amplifier is installed in the speaker box. If you do find amps, take a close up look at the capacitors on the boards for leakage.

TOM,
T&D ELECTRONICS
tdeser@zoominternet.net