Your connection MTU do you have it set MTU: 1500
Ping test your connection with ping plotter from bbc.co.uk it might show the problem.
For use of Ping Plotter no need to register just click [Register] then click [Do it later] you copy result as text file.
My connection test result� Average = 10ms
Target Name: bbc.co.uk
IP: 212.58.241.131
Date/Time: 02/01/2013 22:24:01
1 0 ms 0 ms 0 ms 0 ms [192.168.1.1] Default IP address displayed
2 6 ms 6 ms 6 ms 6 ms [213.1.112.126]
3 48 ms 6 ms 8 ms 6 ms [213.1.115.238]
4 10 ms 10 ms 10 ms 9 ms [213.1.78.74]
5 12 ms 10 ms 10 ms 10 ms [213.1.67.252]
6 * * * * [-]
7 10 ms 19 ms 10 ms 11 ms [87.237.20.244]
8 11 ms 10 ms 11 ms 10 ms bbc-linx.pr01.thdow.bbc.co.uk [195.66.224.103]
9 * * * * [-]
10 N/A 11 ms 10 ms 11 ms ae1.er01.rbsov.bbc.co.uk [132.185.254.46]
11 13 ms 14 ms 11 ms 14 ms [132.185.255.60]
12 11 ms 11 ms 11 ms 10 ms [212.58.241.131]
Ping statistics for bbc.co.uk
Packets: Sent = 4, Received = 4, Lost = 0 (0.0%)
Round Trip Times: Minimum = 10ms, Maximum = 11ms, Average = 10ms
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