Thanks for your reply.
The SB is a Pinnacle HomeMusic. It only has wireless.
I have a D-Link G604T broadband router (2 actually – one that’s on the WAN and the other is spare but is the primary wireless Access Point).
The D-Link has this firmware: V2.00B07.AU_20060901
The SB has the latest firmware – which was picked up automatically from the net when I started the unit.
There is a single LAN – 10.0.0.0/24.
The SB is assigned a fixed IP address via DHCP on one of the routers.
Hope that helps.