My CX is doing the exact same thing. It beeps as the case flexes from one direction to the other. Seems to be worse moving it forward and back versus side to side. It is on it's way back to Garrett. I'll post my results. Couldn't happen at a worse time! It's tectin' time!
Well, my CX is on it's way back to me, I should have it on the 11th. I was told they re-wired the bulkhead connector for the coil and then re-calibrated the unit. Sounds like maybe a wire came loose from the inside side of the coil screw on connection. When I get it back I'll let you know how it works.