HP Thunderbolt Dock G4 stops working in operation, loud sound from fan

[MichaelUray]

I have 4 HP Thunderbolt Dock G4 docking stations which stopped working during the operation.
The fan did run up to a high speed and it lost its connection to the laptop.

I assume an update happend, which got then interrupted by the users causing a power cycle, but I am not sure where the update comes from. It did not come via WSUS, die Windows Update history shows no relevant updates, nor the HP Support Assistent history.
No idea yet, where (if) this update came from and why it is causing problems.

With a HP EliteBook 840 G6 it recognizes the DS if an additional power supply gets connected to the laptop, otherwise no and it get not charged (did not work on this way with a HP ProBook x360 435 G10 laptop).
I have tried to re-install the latest firmware on this way, but it did not help.

Any ideas?

[MichaelUray]

I have four DS with issues in total and I got two of them back working.

The other two respond at least when they get a supply (back-feed) via a laptop with additional external power supply, but it did not help to re-install the firmware update.
I guess there is a power supply controller unit inside on which the update failed and even with the back-feed power it is not possible to update it. It looks to DS works in general with the back-feed power, but it does not provide a power supply to the laptop without it.

[MichaelUray]

How can I actually download older versions of the firmware?

In the download area is only the latest version shown:

https://support.hp.com/us-en/drivers/hp-thunderbolt-dock-120w-g4/model/2101085539