I rtecently picked up a used Rothstein V6B Varitone. It's down at the bottom of the page on this link Rothstein Guitars • Serious Tone for the Serious Player This unit has has 6 settings: 1. Bypassed - this is identical to a tone knob in full open position. 2. Mild treble cut - this is identical to a tone knob set near the halfway point. 3. Full treble cut - this is identical to a standard tone knob set at maximum treble cut. 4. Mild mid scoop - great for slapping. 5. Full mid scoop - great for a "modern" hard rock tone. 6. Dark - rolls off lots of treble and mids. Roundwound strings will sound more like flatwounds at this setting. I'm getting distortion which becomes noticable and worse as I move through the positions from 1-6. Any ideas?