When I was running Jetpack 4.6 my fan would turn on and off and change speed depending upon load but since updating to Jetpack 5.1 the fan turns on at max as soon as it is powered on and stays on flat out.
The noise of the flat out fan is distracting when developing how can I return it to only run when under load??
FYI,
this is known issue with JetPack-5.0 Developer Preview version.
since the fan speed is controlled by the nvfancontrol systemd service. however, it sometimes the nvfancontrol service is started before the required fan driver gets loaded, which makes the nvfancontrol not able to control the fan speed.
you may workaround this by issue the command $ sudo systemctl restart nvfancontrol to resolve the issue.
furthermore, we have fixed this issue in the next JetPack public release.
thanks