I shall post a sample, or at least a capture photo of the wav form. I really don't think it's wind rumble though. While there were overhead fans in the room the last time it happened, there was none the first time around. Plus, I slapped the windscreens on last time due to the fans. I think it's UA-5 or the right XLR connection on the UA-5. Impossible to test because it doesn't happen all the time.