So my 1 year old PF 210HE speaker cabinet started making a buzzing sound tonight at rehearsal. Most prominently on A -880 notes, but sometimes other notes, and definitely not most other notes. Was playing at low volume, and have never pushed this cabinet very hard, ever. I popped the top looking for something loose that might be rattling. When I held my palm against the magnet on one of the 10's, the buzzing would stop. Is there an easy fix for this? Professional repair, or replacement? Any ideas would be greatly appreciated!