Killer Ringing Noise in 1990 740
 

Hey Guys,
I'm new to this forum and have a 1990 740 (the old family car). I've been having this problem where the ringing noise that begins when you put the key in the ingition continues after I've buckled up and closed all the doors. And once you get driving it doesn't stop. One day I had the left rear floor panel of the truck off to get to the antenna. When it was off I unplugged a set of wires to make the work easier and for some reason the ringing stopped. So for a few weeks no ringing! YAY!. Then last week it randomly came back again. I got out of the car and plugged the wires and unplugged them after a few sec. it stopped. However now the ringing continues whether the wires are plugged or not. The other day it would randomly start and randomly end. Now it doesn't seem to be ending. I no longer can blocked it out with musichaving only have one working speaker. Any suggestions on how I can end this pain. I went to bed last night I woke up hearing the ringing.