Over the last few years I have migrated from a trusty old 2600 to a 2820Vn and now on to a 2850vn in preparation for the imminent arrival of Infinty in the next few weeks. This will need an ISP change as Demon carry their traffic for ADSL2+ and faster over C&W who aren't on our local exchange.

I have noticed that at each router migration the inbound data rate has been stable at around 5Mbps, but the outbound has dropped 80-90kbps on each change. The 2600 gave 380kbps, 2820 around 280kbps and the 2850 only 210kbps! The routers all happily synch at 7616 Kbps inbound and 446kbps outbound. SN is typically 10-12dB and Loop Attenuation around 34-36dB. We're approx 2 miles from the exchange via road underground cable route.

I've left everything as default on the ADSL setup, but something is obviously not right at each change point. Anyone got any ideas as to what the issue is likely to be? I would go back to the 2600 except it's long dead and we need wifi. Have Draytek screwed up again, or is it a simple setting change needed? Line is BT provided and has no known issues. MTU is set at 1442, but I have no idea if this affects the outbound rates. LAN is all Gigabit and the rates are common whether directly connected via the router network ports, or on the LAN switch.

Anyone hazard a guess as to where to look?