I didn't have to do anything other than to pair them up. Can you command the unit to dial a number (via voice)? (if so the headset mic works....)
I just checked the manual and there is no way to change the mic level, only speaker volume.
Are you sure you phone is supported my the module?
http://www.harley-davidson.com/cp/moar/en/xmsr.asp1 ) then click on right side "optional components" table ==> "Bluetooth Handsfree Cell Phone Interface"
Look at the table at the bottom of the page ordered by provider. Maybe time for a new phone....
I have a 3/4 Arai Helmet and J&M audio installed. People say the calls are clearer than when I'm sitting at my desk at my home office. I only wish the helmet would mask out the roar from my V&H ovals.......
Mark