I've got an Ampeg SVT 4 pro in need of a professional tech. I've taken it two 3 people here in Columbia Mo and no one knows what they're doing. I've been trying to get this thing fixed for months and the Ampeg website is confusing as it only has phone numbers but no location for repair shops. Customer service has only recommended this website when emailed. The first shop said it was an input selector switch and couldn't get the part. The second just blew the dust out and the switch worked again,but It started having a short and would lose a lot of sound. When I jiggled the volume knob it would cut in and out. The third replaced the volume pot and now I'm barley getting any sound. It was an expensive amp so I'd like to get it repaired but I'm just limited on knowledge of electronics and would like to find an Ampeg certified tech I could drive to.