Internet pausing

Hi guys,

Ok so i have 3 Pcs hooked up to my router (which is a belkin), its a 2meg connection (isp is virgin), two desktops which are wired and one laptop which uses the wireless. The router worked fine for the first few weeks but recently iv noticed 'time-outs' where the internet stops responding for 10-15 seconds and then comes back as if nothing happened. This happens on all 3 Pcs both wired and wireless. Two of the pcs use Xp and the other uses vista, neither of them show any network problems while one of these 'time-outs' is happening.
Any ideas on what could be the problem, iv phoned virgin and they say my line is fine so im guessing it has to be my router, thanks for any help.