Question rear humming noise

[Bob24]

My C6 converable has a humming noise in the rear. Always stays the same even when driving. When I stop the car and turn it off the hum stops. It does not affect the operation. What could it be?

 

[Murray20c8]

My C6 converable has a humming noise in the rear. Always stays the same even when driving. When I stop the car and turn it off the hum stops. It does not affect the operation. What could it be?

I have no idea about Corvettes, but it sounds like a pump of some kind. Fuel pump?