The type of sound seems to me like a hardware, and not a network/interference problem. I've had the PLAYBAR for about a year now with no issues up until 2 months ago. Two surrounds are connected to the PLAYBAR. No sub is used. A BOOST sits in the same room as the PLAYBAR.
Diagnostic number: 8089561
No 5000+ phyerr events are shown when the sound occurs. Network matrix is showing OFDM ANI level 9 for one of the surround speakers attached to the PLAYBAR, which I believe is due to a new Wemo plug installed in the past 2 weeks. However, the buzzing sound on the PLAYBAR occurred before the addition of the Wemo plug and the increase in OFDM levels. The OFDM levels for the PLAYBAR itself show 0 when the buzzing occurs. Therefore, I don't believe this is due to wireless interference.
Best answer by Ryan S
I concur. It's sounding like a problem with that unit, which we'd be able to help with on the phones best.
Also, really great troubleshooting and analysis. Generally speaking, wireless noise shouldn't cause what you're describing. A buzz is more likely to be caused by a power related issue.