How do you set up stable filesharing to a Soundbridge?

I have a new HTPC running Vista Premium. I also
have a XP notebook, 3 other XP machines, a
Netgear router and 2 Soundbridge media devices.

I have my media files on a network drive (Maxtor). All
have worked flawlessly (but a bit noisy), playing the music files
on the network drive with the XP notebook
running WMP11 as music server on the media
devices.

With the new Vista machine, sharing is
stopped. I have tried all the tips I have found,
setting rights to accounts, creating passwords
on all accounts, editing the registry and
manipulating services.msc.

I have on occations
had it all running, but soon discovered that
sharing is stopped again. I then imported all my
music to the local share folder on the vista
machine (clogging almost the entire harddrive) trying to share from there,
but the
problem remains. Sharing is allowed for a day or
two, but is then stopped again.

It can be fixed
by deleting the library and recreating it, but
only for a short time. Microsoft has a guide
describing how to set up anonymous login for
sharing files on another computer, but I have
not managed to set it up (a rather complicated 5
step process). I have not found any guide on how
you set sharing up with the media files on a
network drive on the whole planet.

Some have stated that media
sharing to a soundbridge should work out of the
box with vista but in my case, is it not true.

The XP notebook can still share without a
problem. Windows firewall and sharing with login
is turned off. Maximal permissions is set in all
accounts. I have tried everything I can think
of. Am I the only person in the world with Vista, a media device and a
network drive?

Any help would be much appreciated.