@arnie_oli , @jonesy21 : Quick question (not necessarily a fix), could you check your setting for 'Match frame rate' in Settings - Audio & Video? If you change it to the opposite of what it is currently set as, does the issue remain or go away?
Not wanting to jinx things, I've run a complete factory reset due to newly appearing Prime Video errors, and all appears well at the moment. I also had to restart the hub (v3) as network speed went down to atrocious levels for no apparent reason.
Netflix reports software version 4.35_76_20210916060857... (yada yada etc) UI release 20211123_18925... (yada yada etc) Box itself now on v4.35 (app 76_2021091)
Sadly doesn't really tell me why the issue started or stopped.
Hmm... well now I'm getting an CS2401 error after going out of Netflix and wanting to go back to what I was watching. Saved programs etc report same issue diagnostics report connection speed is now slow. The box also reports CS9994... There's no issue with our network here as I'm responding on here using the same wifi, hub reports a tested 655mbs downstream and 30mbs up so I'm guessing this is a VM issue and not down to us.
A few releases ago we introduced a feature (Match frame rate) that is designed to allow the STB to match the frame rate of the content being played out. The STB/HDMI is defaulted to 25 frames per second as most content in the UK plays out at 25 fps, however some content on Netflix (and Amazon) plays out of 24 fps (and potentially other rates). To the observant eye, this may be noticeable, therefore this setting allows the STB/HDMI to reconfigure to match the frame rate of the content e.g. 24 fps. Unfortunately changing this config results in a blackout of around 5-6 seconds if/when the frame rate changes.
Therefore we provided a user defined setting giving you two options:
Keep the 'Match frame rate' setting set to 'Off' (the default) and accept frame rate difference (not noticeable by most)
Set 'Match frame rate' to 'On' and accept a blackout where the STB/HDMI reconfigures
NOTE: This pretty much only impacts some Netflix content.