Con or legit?

[Stratmangler]

Virgin only mention Youtube and Netflix as being available in UHD if you subscribe.
BBC iPlayer isn't mentioned.

A V6 box landed here a couple of days ago, and it interrogated the TV to see what resolution it could handle.
You could get the box to talk to the TV again, and see if it does UHD.
If it says no, then it could well be the HDMI cable.

[Stratmangler]

In amongst the bits and pieces in the box my V6 box was supplied with was a Cat6 patch lead and a high speed HDMI cable.