I haven't used my NowTV box for a few months but I've just restarted it for the F1 season. When I turned it on, it did a firmware update. However I went into the settings to check the settings and screen resolution and made sure it was set to 1080p. At this point, the output flickers, turning off, then on, then off, then on, and so on, going on and off a few times per second. Auto-detect comes up with 1080p.
When I force it to 720p, it works perfectly.
This is definitely a bug in the latest firmware as I tried it with two identical NowTV boxes, both of which did the same thing. They both used to work perfectly with 1080p on this TV (6 months old Panasonic 4k TV which works fine on 1080p from other sources).
As NowTV is only streamed in 720p (where's 1080p? 4k??) this isn't a deal-breaker but if others find this problem, just force it to 720p.
Hope this helps,
Are your nowtv std boxes on firmware ver 8.0.3 ?
Once my std nowtv box gets the newest update (I am still on ver 7.7.3 at the mo) I will check my Panasonic 4K TV to see if I am also suffering from the same flickering picture when I set the box to 1080p).
One quick thing you could try under the Panasonic TV menu under Settings > HDMI Auto Settings see if changing from Mode 2 to Mode 1 or vice versa makes any difference (I doubt it, but it's worth checking).
Yes, they're running 8.0.3, build 4181-10.
Just tried the HDMI mode and it still exhibited the same behaviour. Worth a try though!
As I say, this all used to be fine, so Sky/Roku have changed something in the firmware that breaks 1080p output, at least in some cases.