Welcome to the Community Forum and thanks for your post. I'm sorry to hear that there's a problem with your Netflix picture quality.
I've been able to run remote testing to your equipment and can see that there is an area issue that could be causing this issue:
Description: You might find that your Virgin Broadband, Virgin TV or TiVo® interactive services are a bit slow at certain times of the day.
Status: Our engineer is on site and they're working to fix the problem.
Estimated end time: 08 FEB 2017 16:45
Please be aware that this is an estimated time frame, while we are working to resolve the issue as quickly as we can, complexities with the fault may cause the estimated fix time to be extended. When work is completed, any slow broadband speeds and buffering on TiVo apps you may be experiencing (particularly at peak times) will be resolved.
I'm sorry for the inconvenience this causes.
Virgin Media Forum Team
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