Last couple of times I have used our BH, the microwave has had a loud vibration. Last time out, I removed the oven and tightened all of the screws that I could (a couple had heads that looked like a star). When I put it back, it sounded normal.

This time out, the microwave was making the same vibration noise and I once again removed it and tightened the screws. This time, it didn't work.

Anyone have an idea of where a vibration could come from and how to access it?