After all my bragging about my little Hartke rig, the head laid down at rehearsal today. Intermittent contact at the input with lots of scratching, popping and very little sound. We stuck my little backup GK RB400IV on top and away we went. Guess I'll bring some contact cleaner home tomorrow and hope for the best. I was growing quite fond of that HA3000 after putting it back in the rack last month. I bought it in 2005 and it's never given me a lick of trouble until today.