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?