Hello! Before I take this amp to a tech I want to see if anyone can shed some light on a problem it's been having. So I was jamming at band practice when some idiot decides to trip over the power cord to my amp, unplugging it. After putting it on standby for about 5 minutes I turned it on and noticed it's volume was only about a quarter as loud as it previously was, and it sounded like ass. I checked out the pre amp tubes and noticed the 2 left most (looking from the back) were not lighting up at all. Also the three right most power tubes seemed to be very slightly dimmer than the left most. I had an extra set of pre amp tubes lying around so I replaced all of them and the 2 left most ones still wouldn't light up, I haven't changed the power tubes yet. The amp is stock except for a Deyoung transformer and only about 6 months old. The preamp tubes are as followed (from right to left): ecc83, gt-12ax7, 12ax7-lp, 12ax7-lp. Power amp tubes are all 4 sovtek 5881/6l6wgc. If anyone has any idea what might be the problem I would be very happy, I want to again!