I just bought a used L6 spider mkii 2-12 model.  I have an older spider valve but wanted the new features.  It sounded great when I tried it out and then brought it home.  Suddenly, the sound got very dirty, then quieter, then gone altogether.  Wasn't too hot.  Wasn't playing loud.  There are L6 repair centers in the denver area but I'd like a theory for you guys as you know your product.  FYI, I always was a "tube" guy and liked the concept but any time I played through an L6 it just wasn't what I wanted to sound like.  I auditioned with a band about a year ago and the guitarist had a L6 spider valve and was playing a no name guitar through it and it sounded great.  I played my guitar through it and bought it on the spot.  I tried the mkii with the newer features and decided to get a newer model.  So I think you have a great product, but it will need to work most of the time.  Any advice if I can fix this myself, where I can buy the parts or where I should take it in the North Denver area. 

thanks

dvd