Topics not loading for some members ?

[scotty-ssc]

Hi guy's, not sure what this could be so will open it to you all, My site is running smooth for me and 500+ members but Iv had 2 members saying that it's gone very slow. The index will load ok but the Ajax shoutbox just sticks on loading & when they go to view a topic it hangs and just says loading They have tried IE/Firefox/Oprea and it's the same on all. Topics are taking that long it times out before it opens, no mods have been installed,
PS they say all other sites are working fine and the home page opens fine, just the forum they are having problems with... bb3

just wondered if anyone has come across this before ? ( I would say its there connection but with it being 2 active users im not sure )

[scotty-ssc]

Anyone got an idea what it could be ?

[scotty-ssc]

Looks like its a BT thing maybe im wrong but it looks that way tonight