to the forums!
If you have a stand alone modem, i canl check if you are on an oversubscribed router if you can pm me the mac address of your modem with your postcode and the first line of you address.
I am sure one of the mods/admins will verify that i work in technical support
When you say it is 'obvious' that you are on an oversubscribed router what has led you to this conclusion? have you spoken to technical support?