I see in the manual that I can select between voice, tone, or voice + tone, but no "off." The prompts mute any music playing and are really annoying. I'd still like the flexibility to hear the prompts when the navigating gets challenging, but rely on the map only showing turns for routine use. I did some searching on the Forum and see that the volume of the prompts can be adjusted by changing the volume control when the prompt is occurring. Will this method allow reducing the volume to zero and avoid interruptions to the music? Or, is there a way to do this in Forscan without permanently disabling prompts?