After a day or two the led stop working (they are black) on videos. i have to reinstall old/new/new addon from repo. does someone have this problem too? maybe i have to do a clean install because mine is really old and many test-versions got tested 
maybe someone else has this problem too and its a bug. maybe i can do a log but its hard to do so beause its all good for a few days until leds just stay black on video…
Can you check if this setting does exist if the led stopped working:
"instCapture": {
"systemEnable": true,
"systemPriority": 250,
"v4lEnable": false,
"v4lPriority": 240
},
Yes it’s already there.
Edit: I got a new workaround:
reboot twice solves the problem too.
I did a clean install. Now i get a different problem -.-
On reboot, leds stay at last state until KODI starts. Then they get black and stay black until i “disable and enable” hyperion via web interface. Most time it behaves like this, some times it starts normal.
What can i do/try?
ive installed latest CE Nightly and latest Hyperion.NG on my S912. running an Ardunino Nano directly on ttyusb0 with Adalight-FastLED-1.1.5 Sketch.
to use the Adalight with 4K and HDR i am using this command
echo 3 | tee /sys/module/amvdec_h265/parameters/double_write_mode
without this command the led’s dont work when playing 4k contend.
random sideeffect is that this command seems to double the brightness!
i must setting the brightness to 35 (normal 70) for not burn down my eye’s
any workaround, bugfix or other to use 4K HDR without this command?
As the base of the source have done a big jump it would be the best to create a new hyperion config from default. Maybe you have a “old” parameter what stopps hyperion.
I made a new config on setting up the clean system. Hyperion itself is running (webconfig is accessible) just the leds turn black. Maybe booting from Emmc is to fast or something? Maybe I have to delay the start of hyperion?
I do have also only one config what is working. When something get changed by hyperion Webinterface it stop working. When I overwrite the config file again it restart working again. When I have more time I will take look what causes this issue.
Sry for my stupid question, is there now a workaround for slowdowns?
Is there somewhere a how to?
Just updaded to 9.0.1 nothing changed 
Use S905x with arduino leonardo and 4k mkv (lokal and nas)
This is not in 9.0.1. You need a nightly
Somewhere a instruction how to do it?
With Hyperion Version 100.3 everything is working fine (led´s start working on every reboot (10 times out of 10)). Thank you so much @Portisch!
May I use on nightly 9.0 Hyperion.NG 9.1.100.3? (or I must use 9.0.100.1?)
I use amlogic grabber.Slow down of Hyperion.ng
Yes use the latest.
S905 CE Nightly 9.0 with Hyperion.NG 9.1.100.3 over wifi esp8266 with led strip ws2812b. No slowdowns, but lot of led turn offs. (full blank)
The command is needed every day? (nightly is forced autoupdate)
mount -o rw,remount /flash && fdtput -t i /flash/dtb.img /amvideocap max_size 64 && sync && reboot
How to disable hyperion when video is not playing? In my case the leds are full time on. In hyperion (not ng) there was an option to disable leds in menu.
I use the black screensaver, so if i don’t use the tv box in 3 minutes the screensaver puts the screen in black and the leds turn off, I have my box full time on but only have ambiligjt when I use it.
How was the feature looking? What option was it in Hyperion?
And when it got disabled? When OSD in front, background video playing?
Or only if no video is playing?