Ok, so at first I thought it a one off... then I thought it as a result of firewall/virus software, so dissabled, along with every other background task, but it continues to slutter. The system is my Dell Studio 15, which should be able to play SD BBC Iplayer, yet after a defrag, running a fairly clean install of Vista Home Premium, through both firefox and chrome, with no background services running still slutters.

Any ideas why??