Strange bonk sound since updating to Big Sur 11.4 on MacBook Pro - even if all notifications are off.
Recently I updated to Big Sur on my MacBook pro, and now ever so often it makes a bonk sound. Its not connected to any notifications that I see. I turned off all notifications both in control system preferences as well as in Mail. Still makes the sound. It does not happen on boot up, nor when opening apps. Anyone have any idea what is causing this or where else to search?