We upgraded these amps to freshen things up since we haven't in 10+ years. We understand that for those of you who may have the other model amps that this may put some stress on you if you are trying to add to your existing set-up. We are trying our best to appease everyone we can while being innovative and keep SoundQubed from being stagnant. If there is anything we can do to help please let us know. You could have warned your existing customers of the change. We had a huge blow out sale on the existing amps and told people the change was coming - Did you recently purchase an amp or is it an older amp?