I get a sound exactly like email notification every hour. I have turned off every possible source of notification sounds I can locate, but cannot stop this hourly chime. I have noticed that rec task is scheduled hourly in task scheduler but cannot fine any indication that it has a notification button. I can, and do, mute the speakers for most of the day but when listening to audio/movies the sound comes through the speakers loud and clear.
thanks in advance for your help
Is your email client settings set to check for emails every hour and also sound a chime ?
I don't know what that scheduled task is you refer to, but you could delete it to see if any adverse effects, put it back if needed.