@harjman
Can I just check a few very specific points here please...
1: Thus far you have said BBC1-SD, BBC1-HD & BBC2-HD are the affected channels. Are there any others?
2: You can use OnDemand & streaming services from your V6 - yes? By this I mean any TV viewing that is carried over the internet - OnDemand programmes, streaming apps such as iPlayer, YouTube, All-4, My5, ITV-app, Netflix or Prime.
3: When you say you have no issues with broadband - when using a wired device, are you getting download speeds that are reasonably comparable to your contracted speeds?
4: When did your picture problems start becoming apparent, roughly?
Edited to add 5: Can you follow, on your V6... Home > Help & Settings > Help > TV Care > (top of screen) > TV Speed test. And confirm the results on here.
We may yet need to clarify some further bits, but if you can clarify these 5 points for now - it would help.
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