Having trouble with my Vaquero , when I turn the ground balance knob either way when Ground Balancing it screams at full volume until I stop turning the control, before there was silence whilst turning GB , but not now, it still ground balances but the noise is so loud it attracts attention and is way annoying ! At first I though it was at the end of turns ie: gone to far one way on GB control but not the case .....anyone had this happen and if so .... please help .