I can see in a previous thread (https://community.virginmedia.com/t5/Virgin-TV-V6/Sound-Break-Up-especially-on-Sky-Film-Channels/m-p... ) you were advised to try watching some affected channels live and to see what the outcome was - I don't think I can see any follow up to that.
You seem to be describing, give or take, the same issues again, so I would emphasise the same test. Pick an affected channel (makes no odds what it is) and leave it running live for a while. If you get pixellation - you most likely have signal issues.
If there's no issues, then pause the channel for 30 seconds or so, and watch it delayed for a while. If you didn't get pixellation before but do not, I would suspect hard drive issues.
I don't know who advised you to check the RS Error count, but as far as trying to diagnose TV faults go, I strongly suspect that's overthinking it and missing the basic tests, The same goes for querying what fixes a local field tech should be doing - let's cover the basics and see where that sends the "train of thought".
Reading between the lines of what's been changed, you've already had a re-pull which is quite often the last resort in troubleshooting network issues. If my suspicion about this is correct, then that's not something that's undertaken lightly.
If you wait around here for a couple of days, VM forum staff should be able to run some remote diagnostics on your kit and see if any problems are apparent. But I really do think that the monitoring of live, then delayed, programming will be a great help in seeing whether your issues are more likely to be on your incoming feed or hard-drive related.
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