Notebook Audio

Hi, 

I'm an IT Technican and we've got a problem with this model of laptop : HP ProBook 440 G6 Notebook PC. 

Since the end of January, the sound and the microphone turns off automatically.  Everytime I look into eventviewer, I never found something signifiant who can cause the problem, I don't even find audio services in the event.

I try several things : 

- Install driver from few sites : HP, intel & Realtek.

- SFC /SCANNOW

- Install Windows update (latest)

- Install Microsoft store updadate app

- Install software's addon (HP Audio Control)

- Update bios (latest)

- desactivate Fn options

 - Autolock Fn

- Uninstall Synaptics driver (I find on another site, last comment : https://answers.microsoft.com/en-us/windows/forum/all/windows-10-randomly-sends-me-to-the-lock-scree... )

- Install update from HP SUpport Assistant

- Install update from a link sent from a HP Techician : https://support.hp.com/us-en/drivers/selfservice/swdetails/hp-probook-440-g6-notebook-pc/23200928/sw...

- Remove every permission, exept for software needed like zoom, to access microphone (Win 10 setting)

- Remove autorisation to access full contron on microphone and speaker

- Install malwarebytes (found nothing)

- Install older version of zoom (even if the application is closed, I still have the problem)

- Try on another account (same problem)

- Ccleaner on registry and tempfiles

- Remove options from advance tab "priority" and do nothing on tab "communications"

At this point, I don't know what else try to solve our problem. I hope you guys can help me. 

Thanks in advance,

Charles.