Juddering on Live TV & Recordings


Set language to US English, 50Hz & rebooted

seems consistently silky smooth but saw brief break-up when skipping & scrolling text glitching frequently at 18:52 & submitted diagnostics

Closed app & went back in, glitches largely disappeared but getting intermittent, very brief glitch in text but overall still very smooth at 19:05

Video of the 1st major glitching: https://photos.app.goo.gl/yxUYnoqnZ1tJmyZK6

Video of minor, occasional glitch (about 14s in): https://photos.app.goo.gl/xpmYCf7GsgDEr2sk8

(disregard juddering in above videos, it’s smooth on TV)

Changed back to UK language, rebooted & glitching disappeared but juddering returned

Definitely looks like you’re on the right track to fixing it


Another observation on another recording (SD)
20:08 - green flashes in US English language 50Hz

Changed to UK language 50Hz & green flashing disappears, also no green flashes when watched on PC with VLC


Thanks @Stuart_Fagg!

So there’s no judder issue at all when in US mode?

Do you know how to sideload apps? Can you install https://github.com/mpv-android/mpv-android/releases/download/mpv-android-2018-04-29/mpv-android-2018-04-29.apk and then use Open URL to try to play from your tuner (http://x.x.x.x:5004/auto/v101)


Playing now with that app & url, looks smooth but colours off & blurred

Yes, US English is judder free but has the glitches


In the settings for that app you can turn off hardware decoding. Try doing that and see if it plays smoothly without judder and without other problems.


Will do. Is there any way I can view a particular channel. Ideally I’d like to check a news channel with text ticker?


Yes, change the 101 at the end to the channel number


Also with HW turned on in that app, do you get the green flashes?


Lots of judder with HW decoding disabled (much worse than I’ve ever seen in Channels). No green flashes at all but I’ve only seen that on the 1 recording so far with Channels

This in US English, 50Hz


You can try to play back recordings in that app too. It’s a bit complicated, but to find the link for your recording you go to the web UI, and then right-click copy URL on the Watch button. That will give you something like:

then you change the ending to be stream.mpg and enter that URL into the app:


I can browse directly to the file. Will that do?




If you can send me a short recording from the channel which is showing that weird major glitching that would be useful.


I’ve uploaded them to same onedrive folder as before

BBC News at Six 2008-04-23 2018-10-04-1800 had the major glitches (but not been able to reproduce since, just the monor ones)

Top of the Pops 1986-05-29 29 May 1986 2018-10-04-1929 has the green flashing (go to about 15 min for worst)


Seeing some judder with MVP playing the HD recording but not the SD. No green flashes

The HD juddered really badly for about 10 seconds at the start but then minor after that. H/W decoding disabled

Again in US English, 50Hz mode


Where in the BBC recording are the glitches occurring?

EDIT: Never mind, I see in your video the ticker was at 18:03. Strangely I don’t see the same glitches here (in US mode, but 60hz).


I’m only seeing the minor glitches now, mainly in ticker text. It was only the 1st attempt that had the major


I see. That’s even more confusing.

By minor glitches, do you mean only when seeking around or also during regular playback?


During regular playback. Seeing it in 50 & 60 but not 59.94. It only appears to be affecting the scrolling text ATM

Still judder fee mind


In US mode we use “Hardware” decoding + rendering. However, as you’ve seen and several other users reported it causes green flashes for some reason on certain UK channels (something to do with interlacing).

That’s why I switched UK mode to use “Hybrid” decoding + rendering. However, that one seems to have the juddering problem (also related to interlacing).

In the MPV app with HW off, its using “Software” decoding + rendering. This skips the hardware decoder and so all the bugs related to it go away. But that app isn’t deinterlacing so the video doesn’t look very good.

I’ve added a new setting into the Channels app so you can switch between Hardware/Hybrid/Software for easier testing. Somehow the other apps like VLC and HDHR use hardware mode, but they don’t get the green flashing problem. Until I can figure out how to fix that, probably the best mode will be Software (with software deinterlacing enabled).

A new beta is available (v154) with this setting on the Player tab. Switch your SHIELD back to UK mode, and change the app to Software decoding to see if it works well without glitches/juddering/etc.