Aura H2O 2 Aura H₂O Edition 2 fails to update dictionaries or sync after updating to 4.38.23697

[Noirtier]

Hi all,

I am trying to setup two spare Aura H₂O Edition 2 e-readers for a friend and her daughter. I needed to add a new dictionary for them, and so tried to do this via the inbuilt settings UI. After adding the required language, it advises to sync the device to add the dictionary. Syncing the first device resulted in it updating the firmware from 4.21 to 4.38.23697 (on reboot). But it did not add the dictionary. When trying to sync again, I just get the error: "Sync Failed. Please try again."

Updating to 4.38 also breaks compatibility with my Calibre 5.44 install (latest supported on my OS). Is it safe to use the "Attempt to support newer firmware" option in the KoboTouch 2.5.1 driver with firmware 4.38?

On the second device I tried to not update the firmware after seeing the results above. But unfortunately it appears that simply connecting it to wifi must have downloaded the update in the background such that it updated on reboot, without ever having chosen the sync option. And the same issue has now resulted with that.

Happily I have managed to add the desired dictionaries manually thanks to the links provided here:
https://www.mobileread.com/forums/sh...d.php?t=196931

So I am just wondering now if it is safe to leave the devices on 4.38.23697, or whether I should downgrade the firmware or try anything else to fix the sync failing issue? I'm not sure they will need that option for anything, but I'm just worried that it might prevent any future firmware updates as might be desired. I saw mention that there were quite a few issues encountered with these devices and the 4.38 firmware?

Any advice would be much appreciated thank you