Sound from rear brakes?

[cmjb13]

I have a 2007 honda accord sedan. I had the front & rear brakes replaced a little more than a year ago. I noticed today that while stopped at a few traffic lights, while releasing the brake and before pressing the gas, there seemed to be a griding sound coming from the rear. I also noticed this while parked and pumping the break pedal a few times.

My wife thinks something was stuck causing the sound. I have not had it reoccur after it happened a few times. I'm going to keep my ears open for when it happens again.

I was fortunate enough to record it. Do you know what this sound could be? It sounds like a docked boat.

Listen here:

Thanks.