I have it too. Wacky noises, oscillations, etc. There is some chatter that is either underneath the transmission. It seems that the noises stop briefly, occasionally, to check the presence of the chatter, and then resume. Makes me thinks this is some kind of peskies jamming peskies? We've had some high strung antics by the peskies around 6925 last winter, I think. Seems to be ramping back up. This is probably how they pass the winter on whatever port/island they hail from.