XPS 9720, no sound from headphone jack, audio selection prompt won't work, RealTek audio driver installation didn't help

UPDATE:   I checked for available updated drivers, and I installed all of them, including a 2022 version of the Waves Maxx Audio Pro driver that my system would allow me to install. I had installed the latest RealTek audio driver first.   After restarting my XPS 17 (9720) laptop, I now find no difference in performance.  The Maxx Audio Pro prompt still appears when I plug a cord into the headphone jack, but as before, the prompt does not work at all  (clicking on OK does nothing), and I still hear audio coming out of the laptop's built in speakers.

This is not a tolerable situation for a laptop that was expensive at the time, which is barely 2 years old, and which has had all software updates and driver updates installed.

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@DELL-Jesse L​   I spent just under an hour --  a completely unproductive hour -- in a chat with a live Dell support person.  He suggested two fixes or workarounds, both of which involved shutting down my laptop and restarting (and therefore having to start the chat all over again). Neither of those fixes worked at all. The second suggestion -- to use PowerShell to give a command to delete Waves Maxx Audio Pro from my computer -- also did not work. Maxx Audio Pro briefly disappeared from my list of installed apps, but now it's back, and the problem with the 3.5 mm audio jack persists as it did before. This support person also gave me a case number and told me that I could go through Support Assist and resume the chat session where I left off.    Demonstrably false. 

FINAL UPDATE:   I had three additional live chat sessions with human Dell support personnel. The second one used remote access to rummage around on my XPS 9720 laptop. As a result of his recommendations, I permanently deleted MaxxAudio Pro from my laptop, installed an updated BIOS, and restarted my laptop yet again.  Without any Realtek audio driver installed, and also without Waves Maxx Audio installed, the 3.5 mm audio output jack started working again, bypassing the internal speakers when an external audio device was plugged in.   It continued to work normally after I reinstalled the latest Realtek audio driver.  It is impossible to install any version of Waves MaxAudio Pro on my laptop because my up-to-date 64-bit version of Windows won't permit the installation.   BOTTOM LINE:   After about 4.5 hours of online chat and after following instructions to carry out pointless diagnostics and alleged fixes, my Dell laptop will not distinguish any microphone or audio input device that is plugged into the 3.5 mm jack.  Dell has not identified any solution.   The last chat person's recommendation was that I back up my laptop and completely reinstall the Windows 11 OS, on a mere hunch that a software compatibility problem would go away.  I am not going to try that . . . yet.     

Currently, the only way that I can get a microphone to work with this Dell laptop is to plug the mic into a USB dongle,  the Griffin iMic.  I can get it to work with SoundForge Audio Cleaning Lab as the recording app.

I remember that 20 years ago (perhaps as recently as 15 years ago), Dell regularly configured its new desktop and laptop computers with a pair of separate 3.5 mm audio jacks, one for mic or line input and the other for headphones or other output devices.  Those days are long gone.   And Dell has failed completely at providing a solution for how to allow the computer to detect whether the user has plugged an input or output device into the sole 3.5 mm jack. 

Had similar problem on a Inspiron laptop today!!!
In a nutshell:  Audio selection prompt was working OK, Ran in the recommended Dell updates, Audio selection prompt no longer happens. 
(When the line-in jack is inserted - Windows now detects the jack as Head-Phones)

Likewise had a support chat session (a few hours) - they suggested reinstalling the Realtek driver which I did (but also had done twice before - including downloading the latest driver from the support website)

But this didn't work.

Parting suggestion was to reinstall windows (nah! ain't doing that)

Got referral to Software Support - but its going to cost me £48.

Sorry, but I'm not going to pay for a problem that is related to the recommended Dell software update !!!

This is a shame as I was achieving good recording results using the straight forward Realtek Line-In connection... but now I'm in a state of limbo - with no solution to this.

Been a fan of Dell laptops for years, but may now start thinking about alternatives....