SMB support requires access to a local and properly configured browse master.
These "bugs" which people report seem to revolve around the location of the browse master.
Relax is told what the IP address of the target streaming server is, so it doesn't have to fiddle with searching your network for the proper share.
As a result it normally shows an XBMS or other streaming server very quickly.
I've had numerous problems, in that the XBMS streaming server gets "out of sync" in Linux.
If you exit the XBMP app (and I've checked this on the logs) the XBMS server keeps "looking" at the last folder it was in.
The next time you go to the XBMP app on your Xbox, you will only see the contents of the last folder you were looking at. This remains until you restart the XBMS server. Ugh.
Jaxstream does this too.
ccxstream will not compile for me.
However SMB is not prone to this as it searches for the shares each time it is used.