I just came back from a short trip (400 miles) and part of the way back I started to hear a noise coming from the front passenger side corner. It sounded like a valve opening or closing and a hammer noise. There was no sound of air being released and it sounded more like the bar door locks when they engage. It would only happen every few minutes. After about an hour I closed the front shutters (from the dash switch) and didn't hear the noise again. After about 30 minutes I opened the shutters and the noise started again. Any ideas?

Not sure if its related but I just had all the air bellows replaced.