Speaker squeal

Question

I have an amazingly LOUD squeal coming from the left speaker only. When I turn the volume down completely the squeal is unchanged. How can I fix this? If this cannot be fixed, can I just go in and disconnect this speaker? I could then change the setting to mono or just run the sound through my stereo. Currently running it to the stereo does not turn off the sound at the TV, I tried that to just work around the problem.