I own a new 65" 4K TV since Saturday.
For that matter I also bought a Sat>IP server (Kathrein EXIP 418), to make use of my old TV in the sleeping room (without Sat-wireing) - just using an FireTV stick.
I the living room next to my TV I was using a Windows10 HTCP (with integrated IR-receiver) with Kodi and DVBViewer(+Media Server).
But since it was using old HW (A10-7870k from 2014) and such a solutions consumes a lot of Power (70-100W), I insteads decided to go for RasPi with LibreElec and a TVHeadend server.
I recently got everything to work and am not looking back ever since. I really like the RasPi with LibreElec!
But sadly, now that I start watching TV with it, I noticed that I rarely get artefacts on HD channels (like "Das Erste HD").
It happens like 2-5 time per minute. Which would kind of be acceptable (--> my wife also said its fine for her), but is of course not as flawless as I wanted it to be (and the DBVViewer Win10 HTPC was).
At the soccer games (half finals of the Euro) this was mostly seen at the ball, when it was moving fast. Then is was surrounded with those fragments. Or when the pictures complete switches to another scene, then sometimes those artefacts are more widely spread.
The network should NOT be the issue. I have a 1GB connection over Fritzbox7950 on all the devices.
I measures the speeds with JPerf and get the same ~990.000 on all the cables in all my house (measuring from the cellar, where the Sat>IP server is located.
Also I don't get those artefacts using SIPTV app on the LG TV itself (direct .m3u-plaback from the Sat>IP server, not using TVHeadend).
Same with my FireTV Stick using Kodi. No artefacts at all using the same TVHeadend-server running on my new RasPi.
So it's most probably related to RasPi and/or LibreElec.
When I turn on logging one thing seems weird to me: the RAM usage is close to its maximum - although I'm using the 8GB version of Raspi 4:
Also on that screenshot you can see a framerate drop to 40.0. The framerate is 99% of the time toggeling between 50 and 48 FPS.
But frequently it drops down to values like 45-46. And on rare ocasions you can see around 40-42.
I think the cap is 50, because i set my refresh rate to 50Hz.
But where are the drops coming from? The CPU util is <40%.
On my Firestick its far higher (70%ish). And the Framerates are even lower - still I don't see those artifacts.
Please help me!
P.S.: I tinkered with ALL! the settings. Here is my latest setup, which tended to create the lowest frequency on artefacts:
OS: LibreElec 9.2.7 with TVHeadend 4.2
Resolution: 1920x1080P (@50Hz) --> to me the 4k resolution was no better image at all, and I can only use 30Hz for it.
HQ Scaler: 20%
adapt frequency: at start/stop of playback
Sync Playback to screen: off
HW-acceleration: on (MMAL)
Deinterlace Mode: MMAL - Bob