PoE hat fan speed management not working

Hi there,

I have a RockPi4B+ powered by the 23W PoE HAT, which has some stability issues. I’m using the official Debian buster image to run the RPi4B as a server only managed through SSH, but from time to time the server gets unresponsive.
I was wondering if the temperature was the cause of the instability and tried to install the PoE fan management software.
After the install (used the automated install as explained in the wiki as well as the file update to activate pwm0 and pwm1), the fan turns on, but with no success in managing the fan speed.

The command

rock@rockpi4b:~$ sudo systemctl status rockpi-poe

gives the following output

● rockpi-poe.service - Rockpi PoE-FAN
Loaded: loaded (/lib/systemd/system/rockpi-poe.service; enabled; vendor preset: enabled)
Active: active (running) since Mon 2022-07-18 00:32:22 CEST; 2s ago
Main PID: 12189 (python3)
Tasks: 1 (limit: 4566)
Memory: 5.4M
CGroup: /system.slice/rockpi-poe.service
└─12189 /usr/bin/python3 /usr/bin/rockpi-poe.py start

Jul 18 00:32:22 rockpi4b systemd[1]: Started Rockpi PoE-FAN.
Jul 18 00:32:22 rockpi4b libmraa[12189]: libmraa version v2.1.0-20-g9ea5a29 initialised by user ‘root’ with EUID 0
Jul 18 00:32:22 rockpi4b libmraa[12189]: gpio: platform doesn’t support chardev, falling back to sysfs
Jul 18 00:32:22 rockpi4b libmraa[12189]: libmraa initialised for platform ‘ROCK Pi 4’ of type 20
Jul 18 00:32:22 rockpi4b libmraa[12189]: pwm_init: pwm0 already exported, continuing
Jul 18 00:32:22 rockpi4b libmraa[12189]: pwm0 write_duty: Failed to write to duty_cycle: Invalid argument

Not sure why the pwm0 is used as according to the Radxa wiki, on the Rockpi4B+ pwm1 is supposed to managed on the pwm1. Any idea?