Your TiVo should be switched on and out of standby mode. Press the 'Home' or 'Power' buttons to do so. This will help us to determine what you are seeing on screen.
The source is the cable your TV receives signals from, such as HDMI or SCART. Press 'input' or 'source' on the TV remote and select the source for your Virgin channels. Some Virgin remotes let you do this too.
To ensure the TiVo box is properly connected, check that the HDMI or SCART cable are firmly attached to your TV.
Switch the power off at the socket. Wait 30 seconds before switching it on again. The TiVo box will then reboot which can take up to 10 minutes. Doing so can help the TiVo box to get signals from the WiFi Hub.