Hey all, So I've been running an Aguilar AG500SC through a DB410 (@ 4ohms) for a year or so now with no problems. Its exclusively been used as a bass amp, but after buying a TC Electronics Ditto (Looper) the other day, I ran an acoustic/electric Yamaha through it. It was late at night and the gain/master levels were way down, and I hit the -10db button. All was smooth and there were no problems. I powered it down and went to sleep. The next morning when I went to use it I could not get a signal from the amp (still can not). The lights both illuminate, so I feel as if it's not a problem with the fuse. The only way I can get any signal from it is to bypass the preamp and plug into the FX send input. Am I wrong in diagnosing this as a preamp problem? Could it be the input jack itself? Was this a coincidental breaking, or do you think the pedal stressed it in some way? (I feel as if this is not really a possibility, and that it was a coincidence, but I've never really toyed with effects. Have always been a passive bass, direct in player) If it is the preamp what is the most cost effective solution? My father is pretty handy with a soldering gun. Thanks!