I picked up a 45/50 recently and while it sounds extremely fine I notice that the bass and mid controls have no discernible effect on the sound. Signal is obviously going through them as zeroing all the tone knobs removes audio and putting them up returns it. However the volume introduced by the treble control (which works normally ) is double that of the bass and mids. Is this normal? Havn't been able to illicit a response from Cornell over this so reaching out to other owners.