Ghost time keeper? *** Solved ***

This is strange and oh so annoying.  I was recording acoustic guitar using two mics to two tracks.  My performances weren't that great so I decided to take a little break. I shut every thing down and came back an hour later to start again.

I started recording with the exact same setup to the same two tracks and suddenly noticed a noise in the background.  It almost sounds like a bunch of people clapping in perfect time.  At first I thought it was the metronome with a weird setting so I turned it off but the noise did not stop.  I finally isolated it to one track.  It only happens when I have armed the track for recording and turn the echo back on so that I can monitor what I'm playing.  I don't even have to hit record.  The rhythmic sound is happening even when the transport is NOT moving.  As soon as I turn the echo back off the noise stops.

Any ideas?

I thought about this and the only thing I could think of was that something was wacky with the clock.  I loaded up the MOTU config software and discovered that it's clock was set to internal instead of S/PDIF.  Not sure how that could have happened since the only way to change it is to actually start the MOTU config software and manually make the change.  Somehow it must have done a factory default reset.

Anyway ... fixed!