I was playing a gig last night and my 3 month old Ampeg VR head suddenly goes into stand by mode! After the band finish the song bass-less, the amp came back on. We tried another song and half way thru in went into stand by mode again. I tried putting the head on the floor, thinking that maybe I had a loose switch and the vibrations from the cabenit was shaking it loose, but no, it did it again! I finally just went direct into the soundboard to finish the gig, but have no idea why my amp is acting this way! Has anyone else had this problem?