I recorded some audio and took it into Audition... the distortion was really bad, and after about 30 minutes applying every trick I could think of, I was really no further than when I started. One thing, there was a cold-voice spot by a YL for some event on September 7th! Also, I heard a 6-digit phone number. YL had Brit accent. It really did sound typical of an AM harmonic.
The 6-digit telly # and accent make me wonder. And WTH are they running a spot that expired two weeks ago??
Mystery signal, for real.