This may have to do with my bluetooth helmet and not the Zumo, but sometimes when I link the zumo and helmet only, my microphone in the helmet stays on, so I hear all the background noise, which decreases the sound quality. Sometimes the microphone will stay off. I can't figure out what, if anything, I am doing differently to determine whether the mic is on or off. Just yesterday coming home from an over night ride, I had just the helmet and zumo linked, and only one time after a stop, the microphone was off, which is what I wanted. The rest of the time I can hear my breathing, cars going by, etc. Anyone have an idea on how to keep the mic from being on? I read through the manual (I bought this used) but didn't find anything that addressed this.