The TiVo box doesn't support 4K output and you've quoted a V6 software build, so I think you've got a V6 but all the same...
There's recently been a software update to the V6, and if you're watching in 4K/2160p then you must now have HDCP 2.2 copy protection enabled in order to watch VOD programs. If you don't, then what you're seeing, will happen.
Your TV may have multiple HDMI inputs, in which case you may want to try each one in turn to find one that supports HDCP 2.2. If your TV doesn't support this standard, then you will need to reduce your video output to 1080 to watch VOD. You can do this by following Home > Help & Settings > Settings > Video Output, and making sure that 1080p/1080i is enabled.
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