Try disconnecting and reconnecting both devices again. I found that sometimes they just connect out of sync, but can usually fix it up by reconnecting one or both devices.
It's difficult to do and as far as I am aware there isn't a sure way to do it. I also use 2 devices often and sometimes they just sync up on their own usually after the first song finishes.
Yes it is. I wish there was a better way to do it but I guess no one ever brought it up to Samsung. Maybe if enough people were to ask for a way to get it done they would try to find a solution.