VKB-SIM

I have a Gladiator EVO that's a few years old, and very suddenly, the red thumb button on the 'Space Combat' grip has stopped reliably registering a signal. It isn't completely dead, but you have to apply more than the usual amount of pressure, and hold it down for a bit.

I'm prepared to open the thing up, but I haven't the faintest idea what I'd be looking for - I'm a software person, not a hardware person. I see that the official YouTube channel has some tutorials that involve disassembling the grip, but nothing that I could see related to troubleshooting a broken button. Would appreciate any pointers on where to get started.

If I activate the "Poll" checkbox in the Profile-Buttons tab and press the button, does the red square light up easily or only when I press hard?

No, not getting any red square for that button for a normal press. And even the 'pressing hard' seems to be getting less reliable than it was a day ago.

There is such a button there and it means that its electronic life has come to the end, unfortunately.
Replacing it with a similar-sized one at a repair shop (the force may vary, this one is 2.6N) will take 5 minutes. If you don't have a repair shop near you, try emailing sales@vkb-sim.pro.