I have this issue on a daily basis and have had since the channel started. In fact it has just been happening which is why i am online looking for a fix as it drives me nuts.
The sooner my contract with virgin is up the better sick and fed up of the garbage faults with GB news, internet drop outs and the missing boxsets issues that are as bad. Like the other day started watcj[hing F.B.I. season 3 then all of a sudden program unavaliable please try again later then it completely dissapears from boxsets. Virgin need to get a grip.
Firstly, just by means of forum advice - the general rule on here is that it's much better to start your own thread with your own issues and/or not add multiple replies to other people's posts. It saves time in the long run and keeps everything in the same place - I've split both your posts into their own thread and merged them for you 😉
You've mentioned problems with pixellation on GB News HD - do you have any similar issues with Sky News HD, Sky Nature HD and/or BT Sport 2 HD? Otherwise the standard advice for all pixellation queries applies - reboot your box one, and then go down the faults route because something would evidently be awry and likely need VM intervention.
Boxset availability can and does vary from time-to-time, and I can't check my V6 at the moment to see.. is this the only programme you've had problems with, or are there any others?