I am still having the same problem that I had before which is the same as yours.
My whole problem started when I took apart the turnsignal branch off the steering wheel and put it back together trying to fix an unrelated problem.
First the buzzing used to go every 20 secs. Then it became a constant buzzing.
It goes away in reverse, my radio is just fine. When i turn the turn signals on the buzzing will buzz to the beat of the turn signals. Buzz, buzz, buzz. But the turn signals don't work.
I have looked at the turnsignal branch several times, but just cannot figure out what went wrong and where.