One more thing for anyone who actually uses the inner knob, watch out for lowering/attenuating with the inner knob! I believe it is technically possible (I've been meaning to test this, and I think this would prove the inner knob is digital and outer is analog) if you have the inner knob turned to the left to brick the signal without the clipping lights lighting up on the right. So, if you are going to use the inner knob, I think I'd stick with only using it to add digital gain, not to attenuate digitally (personally I see no good reason to even touch the knob at all except to make sure it's at zero).