set key repeat rate of Bluetooth RC

I love the cheap FireTV Remote (modell CV98LM, Bluetooth version) but I have problems with setting up the key longpress repeate rate of it. The method I used untill now on my old libreelec generic build does not work on my Coreelec Amlogic installation (copying /usr/lib/systemd/system/xorg.service to /storage/.config/system.d and adding “-ardelay 5000 -arinterval 1000”)

any method to do this on CoreElec? Please remember this ist not an IR remote.
Zhanx for any replies.

PS: Longpressing of keys does not work too on CoreElec. Neitehr waking up system with BT (all this worked on generic Libreelec 9, with an USB BT Dongle).