I have a V4BH and I love the thing, it just sounds great. One thing that puzzles me however is the "frequency" control on the front panel- which as I understand from the manual is supposed to adjust midrange frequency at various factory presets on the dial. I can't tell if mine works or not, there is no noticeable change in the sound when I move it between the presets. Is it supposed to work something like the "style selector" knob on a BA112 or BA115? If so, there must be something wrong with it, because any change in the sound happening is so subtle I can't hear it... Do any of you other V4BH owners have this issue with your amp? Thanks.