You aren't being shaped, you've a fault on your service somewhere.
If they won't fix it go elsewhere, or alternatively if you don't wish to or are unable to do this you could try mailing the CEO, or taking your issue to the ISPA.
CEO:
neil.burkett@virginmedia.co.uk
ISPA:
http://www.ispa.org.uk/
You've a fault and you're being blagged by tech support that's either too incompetent to or can't be bothered to do their job properly. Sadly it's as simple as that.