Unfortunately no, it doesn't help at all because you've mentioned that you're using apps on your TV directly - this has nothing to do with Virgin Media apart from them providing the internet connection to your TV.
I therefore need to ask whether your problems with YouTube are when you're accessing it on your TV directly, or via your V6 box - because if it's your TV app, again - nothing to do with Virgin Media except that being your broadband connection,.
If we're trying to troubleshoot the YouTube pp on our V6, then forget your TV apps - they're irrelevant. All the tests in my previous post are to be carried out on your V6 directly.
If the problem is with an app on your TV, then the most we can do is ask the make & model of your TV and/or point you towards your TV manufacturer.
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