It does sound like there is a problem.
What happens if you try this speed test :
http://www.cableforum.co.uk:81/board/speed.php
Have you tried downloading something large from the BY games server :
ftp://ftp.blueyonder.co.uk/store2/blueyondergames/
At least that way you're not stepping out of the BY network.
As it's an ftp site, you could also try a better FTP client (
filezilla maybe) than your browser.
You could also try doing a tracert (eg
tracert ftp.blueyonder.co.uk at Dos prompt) to the ftp site and to
www.cisco.com. This might identify whether the holdup is inside or outside the BY network.
An example tracert from my NTL 2Mb line (speed test says I'm getting pretty much 2Mb):
3 22 ms 14 ms 10 ms glfd-t2cam1-b-v107.inet.ntl.com [80.4.30.173]
4 26 ms 22 ms 21 ms 195.182.175.253
5 13 ms 10 ms 9 ms gfd-bb-b-so-300-0.inet.ntl.com [62.253.185.29]
6 12 ms 12 ms 12 ms win-bb-a-so-500-0.inet.ntl.com [213.105.172.129]
7 61 ms 43 ms 22 ms man-bb-b-so-600-0.inet.ntl.com [62.253.185.137]
8 17 ms 16 ms 16 ms mana-ic-1-so-300-0.inet.ntl.com [62.253.188.74]
9 * 16 ms 15 ms 194.117.148.177
10 22 ms 23 ms 24 ms 194.117.136.217
11 23 ms 21 ms 27 ms mirror3.blueyonder.net [194.117.143.71]
This might not
solve your issues

, but it might give a clue where the issue lies