beep

Something keeps beeping when I click nearly anything. It's not a true error alert, as it happens with clicking nearly any proper item. I could not upload a video here, so I put one on Vimeo. It's only 8 seconds. In the video, I start by clicking my browser on the left (MacBook Pro), then...

I run Windows 10 in a Parallels VM (Parallels Version 17.1.4 (51567)) in Coherence mode. Each time I switch from a Mac app to a Windows app, a VERY LOUD BEEP sound is played, hurting my ears when I have my earphones on! This is VERY ANNOYING! Is it possible to deactivate this nasty beep sound?