Ruffcubnj

Has anyone noticed this... With all the rain we've had, I've had the defroster on, and the fan. I have the mtx, so when I rev the engine or just accelerate, the fan noise increases and decreases accordingly. Almost like feedback through the radio. So I turned the radio off, and it's definitely doing this modulating thing. Annoying! Any suggestions? Should I mention it to the dealer. It doesn't seem right.