Raspberry Pi 5 fan HWMON number keeps changing

Configuration
1

I have created a Config entry to enable a monitor for my Raspberry Pi 5’s fan:

command_line:
  - sensor:
      command: "cat /sys/class/thermal/thermal_zone0/temp"
      name: HA CPU Temperature
      unit_of_measurement: "°C"
      value_template: '{{ value | multiply(0.001) | round(1) }}'
  - sensor:
      command: "cat /sys/devices/platform/cooling_fan/hwmon/hwmon2/fan1_input"
#      command: "cat /sys/devices/platform/cooling_fan/hwmon/hwmon3/fan1_input"
      name: HA Fan Speed
      unit_of_measurement: "RPM"
      value_template: "{{value}}"

At random intervals the fan monitor reports as ‘Unknown’, and I have to change the ‘HWMON’ entry from ‘2’ to ‘3’, or vice versa.

Does anyone know why this is the case? And is there anything I can do to stop it spontaneously changing of its own volition?

2

Happened again today. The reading came up ‘unknown’ and I had to swap from hwmon2 to hwmon3. Tomorrow I will likely have to change it back to 2.

Doesn’t anyone know why this is happening, and is there anything I can do to fix it?