I have the uclear 100 boomless helmet communicator that effectively does what you are asking from my iPhone.
So far I am happy with it. I can also hit two buttons and tell Siri to do things for me. Like play a certain playlist. Call some one. Find the nearest gas station.
The phone will mute music when a phone call is coming in. Just say hello and it picks up. Music resumes when you are done.
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2012 650, Centerstand, lower cowl, accessory plug, grip protectors, hot grips, fork brace, mirror extenders, crash bar, auxiliary lighting front and rear, madstad, California Scientific medium windshield.