I have that problem ALOT
But its intermittant, one of the websites is aria.co.uk another is my web host
www.alivewww.com. Which is a right git cuz 1. it means I cant access my email, it just times out, and 2 i cant order stuff form aria, the website times out

but most other sites are perfectly fine.
It MUST be an NTL routing issue that they just wont bother to fix.
Oh also it effects Live For Speed master server list.
So its not exactly a small problem considering the amount of sites, servers this effects on me. This will eventually make me move to a BT based broadband as I am getting fed up with it.
Ive tried different proxy servers, even the new ones but it makes no difference.