As per japitts, "Did you reboot you V6 after changing the video output?" This should clear the issue, if it didn't please try the following.
You can force the screen to reset and it will display in the basic 576p resolution. This will allow you to go into the V6 settings and change the video output again.
Using your remote control press Thumbs Up, Thumbs Down, 4, 8, 0, Clear
You should now be able to see the screen again, so using your remote
PressHome >Help & Settings > Settings > Video Output > Video OutputFormat
Either go toAuto detectto run a test of your TV’s display options. It will then ask you to confirm the new display selection or choose Test Formatsto run a quick test on the Virgin TV V6 box and follow the onscreen guides
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