piCore player - disabling Raspberry LEDs

[newyankee]

I have switched my Rpi 3B+ to piCore 6.10 recently. I have again tried to disable network, power and status LEDs - in the bedroom. I have added these lines to config.txt. It doesn't work. I have the impression that during boot, the LEDs are off for an instance but then this gets overwritten by something else. It's obvious that my linux knowledge is somewhat limited....

#Custom Configuration Area, for config settings that are not managed by pCP.
#pCP will retain these settings during insitu-update
#---Begin-Custom-(Do not alter Begin or End Tags)-----

# Turn OFF Network LEDs
dtparam=eth_led0=14
dtparam=eth_led1=14

#---End-Custom----------------------------------------

How can I get this to work?

Thanks
Guido

[jeroen2]

How can I get this to work?

I run a shell script at startup which, amongst a bunch of other stuff, includes this line at the end:

#!/bin/bash
#turn off power LED
echo 0 | sudo tee /sys/class/leds/led1/brightness &

This turns off the power light after everything else successfully started up.