Samba disappears from Net. Neighbourhood!?

[Jeff Newton]

I'm running 1.9.17p2 on a Sparc machine.  I have an NT server on the same 
subnet that is acting as the master browser.

Every so often I notice that my Samba machine disappears from Network 
Neighbourhood.  Samba continues to run and I can access it but the
browse capability is getting lost somewhere.

Anyone experienced this?  Any idea how to debug this?

Here is my smb.conf:

[global]

   workgroup = pmc_nt 
   comment = Samba Server
   browseable = yes
   netbios name = nt-nfs 
   autoservices = homes
   server string = PMC Samba Server
   log file = /home/cs/admin/solaris/samba/var/log.%m
   max log size = 50 
   short preserve case = yes
   preserve case = yes
   lock directory = /tmp/samba
   locking = yes
   share modes = yes
   local master =no 
   domain master = no 
   wins server = xxx.xxx.xxx.xxx 
   wins proxy = yes

[homes]
   comment = Unix Home Directory
   browseable = no
   writable = yes
   read only = no
   create mode = 0750

[CS-test]
   comment = CS Test Directory 
   path = /home/cs
   browseable = yes 
   public = no 
   writeable = no
   write list = @cs
   create mode = 0755

---
Jeff Newton
Unix Systems Administrator
Computer Services
PMC-Sierra Inc.