Just changed routers and sync speed has dropped by half

[#1]

Hi,
Apologies if this has been dealt with somewhere else but I haven't been able to find an answer.
My old reliable 3Com router blew up in a thunderstorm and I have just bought a new Belkin N Wireless Modem Router. Setup was easy and it works well but the sync speed has dropped from over 3000 to under 1500. I've changed filters and done all the usual things such as restarting the router, but it resolutely stays low.
The registered speed profile has dropped to 1000 and the BT speedtester says 1344, the same as my router reports.
Has anyone else had this problem or able to shed any light.
Any thoughts gratefully received
Toby

[#2]

Can you post your router stats? Guide on here http://www.kitz.co.uk/adsl/frogstats.php

[#3]

Sounds like the lightning did more than just zap your old router, and has maybe affected your copper pair. If you're in luck, IYSWIM, it has, or very soon will, cause noise or break down completely, at which point you can report a voice telephony fault.

[#4]

Thanks very much for your comments.
Here are the router stats, I haven't found the CRC errors and am not sure if the router produces them.

                                                Downstream Upstream
  Data rate(Kbps)
                                                    1344Kb 448Kb
  Noise Margin
                                                            6 18
  Output power(dBm)
                                                        125 173
  Attenuation(dB)
                                                            62 31

[#5]

Do you have extension sockets/wiring? If so try plugging into the test socket and see what results you get. Note - it's best to power down the Modem/router and wait a few minutes before unplugging the line/filter/master faceplate etc to avoid the exchange DLM thinking you have an intermittent line problem.
Have a listen to your phone line, if you can hear any crackling or other intermittent noises whilst plugged into the test socket with the router off then report a voice fault whilst it's crackling and don't mention the broadband.