Long shot here, but worth a try.
I've been using a SB M1001 since Jan. 2006 and Firefly for nearly as long, but recently whenever I restart my PC the SB can't find Firefly. I tried uninstalling Firefly and then cleaning out the registry, then doing a fresh install but the problem persists. I found a newer build (svn_1737) but it made no difference. Luckily reinstalling Firefly over the existing install gets the SB working with Firefly again and only takes maybe 30 seconds (it remembers all of the web interface settings and music library info), but of course I would rather not have to take this step each and every time I want to use my SB after the PC has been shut down.
If it matters, this is running on an old Vista 32bit PC. Anyone know if an automatic Windows update or iTunes update may be the cause of this problem?
FWIW, iTunes still works fine with the SB but I only use iTunes with MP3 for my iPod and iPhone. All of the files Firefly serves are Apple Lossless on a separate HDD.