I having a huge problem with my SVP thats actually making me want to get rid of it . I bought it used and since I recieved it anytime I turn the gain nob on it up beyond a 1/4 of the way it clips like crazy and it always sounds super muddy . Please tell me this isn't normal. All this is with the -15db button pressed in ,other wise it does nothing but clip. I've replaced the tubes in it since I got it and it hasn't helped much if at all. Also what purpose does the 12au7 tube in the older models serve? HHHEEEELLLLPPP!!!!! .