When you refer to All-4, do you mean the branded app or just C4-OnDemand programmes that are branded as All-4? I suspect the former but will check.
I ask because it sounds like your issues may be the V6's internet connection, and testing VoD is one of the checks. If you do mean the branded app, can you check whether OnDemand programmes have the same problem.
Let's assume that's the issue - a V6 connects to the Internet via your Home-hub, which can be Ethernet cabled or Ethernet. What's yours?
In the meantime, TiVo has the same VoD access as V6 if the programmes are available there.
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