Error 603 is quite often an HDCP issue - VM require you to have compliance with HDCP2.2 throughout your V6 > TV chain, if you're watching VoD in 2160
A quick way to test whether this is indeed the problem is to drop your video output to 1080, and force your TV to then do any upscaling from there. Follow Home > Help & Settings > Settings > Video output, and make sure that 1080i/p is selected. You may need to restart your V6 for this to take effect, but it's often ok without it.
If you still get problems, then HDCP2.2 isn't your issue and we need to look elsewhere. If this resolves it, then something in your kit isn't HDCP2.2 compliant.
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