If you have your phone with you, why not just pair the headphones to phone and listen to music from the phone, and then get your calls that way? I get that the novelty of having the music on the watch and being able to use it that way, but it's a big drain on the watch battery. If you pair to the phone, you can still use the music glance to change songs and such (if you don't choose to do that with the headphones).