Your setup doesn’t use firefly.
But let’s see if I know a solution anyway.
You’re playing music on iTunes, and want to reroute it wirelessly to a hifi.
Really, you don’t need a windows mobile device for that. I think it would make it even more difficult.
My first google for “wireless audio” gave me lots of satisfying results.
Unless ofcourse you want to do more than just transfer your music wirelessly, which is why you picked WindowsMobile.
If so, let me know. I’ll see if I can find another solution. 🙂