The odd thing is the manual that comes with the 2004 MCS and the H/K stereo says there is an adjustment. It says you push and hold the tone button until 'TONE LIN' is displayed and the keep pushing until 'SPEED VOL' is displayed. When I tried this I got to TONE LIN fine but then it went to NAV MIN and then to RESET and next push gets me back to radio or CD. RESET, according to the manual is to reset the the tone adjustment.