I went through about a dozen iterations of the pairing process in mating my Zumo 660 to my Droid mini and then pairing that with my SMH10R. I have then linked the intercom to a Scala Rider G9x.
Finally, it worked by updating the Sena software to the most recent, resetting to factory, and making sure that all pairings were erased before starting the process. I did start to question my sanity during the drill as I repeated my actions - but I eventually did get a successful result. It does take about 10 seconds for everything to sync when I first start up.
10 NT 700