slow, stopped and ok sites

[#1]

why every so often do some sites crawl or fail to load when others load fine. Its nothing to do with pages already cached for those that load fine. Tonight the beeb and a couple of others are slow or fail to load every so often whilst others are performing fine. They are all on different tabs in the same instance of firefox. a couple of minutes later they will all be ok again.
Thanks
PT

[#2]

I'm having similar problems tonight.  I've put a ticket in but have had no reponse yet.  I can get to things like Gmail, Face book, the BBC site yet other site are pretty much inaccessible.  I couldn't get on to symantec.com at all.  logitech.com is so slow it's pretty unusable too.  I need to download some software from logitech, after 10 mins waiting for the page to load it told me that the 8Mb download was estimated to take 3.5 hours!  After half an hour (and only 26k downloaded) it lost the connection and I haven't been able to get the download to start since.  I'm starting to feel very frustrated!

[#3]

I had problems with slow loading of sites, last night. Never had that problem before. I disconnected and reconnected the router and all was back to normal. Possibly the gateway I was on had problems

[#4]

I'd rebooted my router but it made no difference   The problem righted itself late last night and it's all been fine ever since.  I still haven't had a response to my ticket though.

[#5]

Its ok with me now too. I didn't do anything with the router. it only happens every so often but its annoying
speeds were varaible last night as well - 2500/350 to 4500/350. Understand demands may slow things but not that varaible over consecutive tests.
normal daytime speeds now - 6500/350