After having tried my luck with 2 Thompson SpeedTouch routers (one being the Be* supplied WL780 and the other a reflashed BT HomeHub) I gave in and bought a Netgear DG834Gv3.
The relevant settings for using with Be*:
- Basic Settings:
- Does Your Internet Connection Require A Login? NO
- Router MAC Address: <MAC address of previous router, or let Be* systems timeout – takes around ~40 mins)
- ADSL Settings:
- Multiplexing Method: LLC-BASED
- VPI: 0
- VPI: 101
- WAN Setup:
- MTU Size (in bytes): 1500