Have you been into the V6 settings to check the way the display is set up?
Also have you tried signing into Service status at the top of this page to see if there are any local issues, and run a test against the TV box? By doing this VM should be able to send a signal to your box and try to repair it.
If that doesn't work then you need to contact the Faults team.
You could try the text messaging service. Just send a text with a description of TV Faults to 07533 051809. Your message will go into a queue and a representative will respond to you as soon as possible.It may take a few days.
You can also call 150 from a Virgin landline, or 0345 454 1111, options 1,1 and 2 (Faults) butbest to call at 8am to avoid call queues
When calling Faults you will go through a series of questions/tests, if that doesn't resolve the problem then call back around 10 minutes later and an agent should pick the phone up.
The Service you do for others is the rent you pay for your room here on Earth - Muhammad Ali
What size TV screen are you viewing on? I tend to work with an assumption that one level of upscaling, say SD > HD can be fairly well done, but if you're then viewing SD content on a 4K UHD TV it's going to look bad sooner or later.
Also as newapollo has suggested, tweak your video settings to experiment with what equipment is doing the upscaling. Say your V6 outputs at 1080p, that forces a 4K TV to upscale beyond that, or the V6 can output at 2160p if it's better that way.
Experimenting with your kit can often achieve good results, there isn't a one-size fits all.
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