Attached link is the recording of sound bar when it is not playing anything. I’m not sure whether that sound is normal or any issues. Anyone who has 700 please check and confirm?
http://www.mediafire.com/file/5anp0jjtuu6er62/New_Recording_…
( When you click this link please view ( not downloading ) it so it will be played directly )
Sounds like a common issue with plenty complaints online. Try a firmware update and changing plugs/cables around to see if it's interference.
https://community.bose.com/t5/Home-Theater/Soundbar-700-and-…
https://community.bose.com/t5/Smart-Home/Bose-Soundbar-700-S…