Macbook Air 2012 single beep while on My MacBook Air 2012 is making a single beep during normal use. So far it has done this twice in the last 20 minutes so I don't know if there is an interval yet.

A cursory Google search only showed something about people having boot issues with multiple beeps when trying to start the machine. I am using this machine (it's already booted without issues) so I don't think that is relevant to me.

The machine isn't running hot, which would also be normal. So what does this beep mean? Insight appreciated.
SoundBunny has a free demo available which will work for 30 days, this app will show you every app which is makes a sound. That might help you track it down. You can also tell it to ignore apps which you have ruled out, which should help you narrow things down a but too. The purpose of SoundBunny is to let you set the volume for each app, but I thought it might help with this as well.

TJ Luoma posted this answer to a similar question here: apple.stackexchange.com.