Thanks for the developing this. I’ve followed the excellent guide Raspberry Pi 4, Home Assistant OS (5.5, dev version) on a SSD, and the Argon One M.2 Case (In Progress) by @FreelancerJ to the point of activating the fan. I’ve run the I2C Configurator and after a full shutdown and restart (a 1st reboot didn’t seem to be sufficient) it looks like that worked:
…
adding dtparam=i2c_vc=on to sda1 config.txt
adding dtparam=i2c_arm=on to sda1 config.txt
no sdb1 config found
no mmcblk0p1 config found
This Configurator did it’s job. You can uninstall and reboot now. This configurator only works once.
As I’m no Pi or Linux expert so this was an easy way to get I2C.
As for the Active Cooling addon, that’s working, the fan is on 
. I was using the default temperature settings where the low is 90F, however I couldn’t get below 95F-98F so the fan was running continuously. I’m not familiar with Pi4 temperatures so just wondering if you have deliberately set a low threshold. The HassOS is only running at just over 1% CPU so not exactly taxed. Anyway after looking at the Pi forums I’ve upped the low (100F) and medium values and it works great with the fan coming on occasionally.
Really happy to be running HA from SSD on a Pi4 device in a professional looking case, all with active cooling.