I've never been with BT but all the ISPs I've used were very keen to help you lower your pings. BlueYonder switched me to another network as soon as I phoned saying my pings were high in the evenings, and Sky actually broke company policy in their effort to lower my pings. I suggest you give them a call, but insist on speaking to tier 3 support (the ppl who actually know what they're talking about and can actually change stuff for you). You'll be asked a lot of useless questions by the tier 1 ppl, but don't let them catch you out (e.g. if they ask if you tried doing this or that just say yes to all) and eventually they should put you through. If they still refuse to help just threaten them with switching ISPs. That tends to work wonders.