Slipstream...
Now are you completely turning OFF the autopilot or just one of the upper pushbuttons on the UpFrontController in the VC for BALT hold? If you dont hit the AUTOPILOT ON/OFF (located on the lower bar of the UFC) to turn it off and get the audible horn sound, then the heading hold may still be engaged? Sometimes, it "sticks" on when I engage autopilot for altitude hold, and I automatically get heading hold til I manually switch the heading hold button ON (: diplayed), then reclick it off. After I do that, I still get autopilot altitude hold, but I regain stick control over my heading.
Hope that helped?
Later
Sludge