Question Gaomon PD1560 tablet shows up as audio input in Device Manager, pen not registering

[Novaria]

I've been having what seems to be a common problem, which is the pen/stylus not registering for the Gaomon PD1560 drawing tablet. It worked perfectly on Windows 7, but ever since upgrading to 10, it doesn't work. The tablet itself shows as "connected" in the Gaomon software/settings, the driver is up to date, and I can use it fine with a mouse as an extension/duplication of my main monitor. The stylus just doesn't affect the cursor on the tablet. Yes, it's fully charged, cables are secure, and the software is set to the correct display.

Nothing I've tried so far has helped, and the Gaomon website FAQs are useless. But I did a bit of detective work and discovered that the tablet doesn't show up in Device Manager as a tablet in the first place, or even as a generic monitor or display adapter. It's under "Audio inputs and outputs" as "PD1560 (3- NVIDIA High Definition Audio)". But I don't think the tablet even has speakers, so I don't know why it would end up there. It pops up in that category even if I uninstall everything and turn off Windows automatic driver installation before reconnecting it. I'm suspecting that's why the stylus doesn't register, but I don't know how to make Device Manager recognize the tablet correctly. Is that something that can be changed in an inf file or the registry or something? I don't know where to begin, and web searches have been fruitless. Any advice or suggestions would be welcome.

I'm using a dual HDMI adapter so I can use the monitor and tablet at the same time, but I don't think that's the problem since it still doesn't recognize the stylus even if I have the tablet set as the main/only display.

 

[Lutfij]

Dual HDMI adapter? Mind sharing a link to the adapter? Or are you referring to the splitter that came with the tablet? Might want to also install the drivers for the tablet under compatibility mode, i.e:
Right click installer>Compatibility tab>Windows 7 (drop down menu)

 

[Novaria]

I've already tried installing under compatibility mode. I've tried pretty much all the first-string suggestions that tend to show up in basic web searches about this stuff. I'm no stranger to wrangling misbehaving hardware, but this one has me at a loss. I'm basically looking for more advanced suggestions, if possible.

The adapter I'm using is this one: https://www.amazon.com/gp/product/B07H11ZHPW
But as I said, the stylus still won't register even if I don't use the adapter at all and plug the tablet directly into the main HDMI port.