Hi. After paying out £140 to repair my Crack + Speedball because it losses the right channel after about 15 mins of play, it's doing the same again. First time the enginer changed a couple of components on the speedball cct board. I was wondering if this has been an issue for anyone else and if so what the possible causes might be? Any help would be appreciated otherwise sadly it will be the end of the line for what was a great amp.