I'm in Calgary and have gotten the 'buzz' on channel 22 (FOX28) Spokane KAYUDT for a couple of weeks, off and on. Today we noticed it on our channel 14 (PBS) Spokane KSPS. Also on channel 16 (NBC).
There may be more channels, but I gave up watching cable TV for today. The buzz is quite loud and to tell you the truth, kind of scary.
The buzz must be caused by the cable (box), because when watching a movie through ROKU there is no buzz.
After messaging Shaw, it was decided to send me a new cable box. When the box arrived the next day I checked the 'bad' channels and lo and behold the buzzing had stopped. I didn't need the new box after all.
Pretty weird experience.
Currently getting occasional buzz on MSNBC