so I bought the Hartke lh500 a in February, the place I bought it from is a dealer, but no warranty paperwork so I thought that they would take care of the warranty registration (as some have in the past) I guess they don't though. anywho I played a gig last night and as I have come to expect from the system it was buttery smooth and sounded as good as it always has. I go to play a show tonight and after I set up all my mica and basses(yeah I set 2 up because my guitar player looks cooler with 2 telecasters hanging out on stage) I turn the lh500 on and everything appears to work fine, but no sound. I checked all the usual suspects but no luck. I turn the head on and off again then it works, but not even as long as the soundcheck before it went out. no fuzz no power problems, just no sound and no fan. I tried to get it to work for a while but I had to throw in the towel and cancel the show. I have a very important show soon and I don't have the time to repair it my backup is a HA 2500, but the tube ballast is bad (like so many of the type) so I cant use it. I bought he lh500 because they said it was road worthy and depedable. is there anything I can do to fix my head before the weekend? or do I just forget it and buy/rent another head?