Hi rich_tweddle,
Welcome to the Community!
Sorry to hear you're having trouble with you TiVo® and our call centre. It's very unusual that you got disconnected from the call, especially twice in a row!
I'd like you to try updating the box for me. Just press Home on the remote control and select Help and Settings, Settings, Network then Connect to Virgin Media TV Service Now.
Leave that for about an hour to fully update then try the On Demand again.
Let me know how it goes! 
Josh
