I have similar issues in a used (1.5 year) Gladiator Mk.II, capt of buttons A-1, A-2, A-3 sometimes get stuck when pressed.
For me this happens is due the fact that plastic spring lever that return button cap up act only in one side, then the cap tilt a bit and stuck.
I fix this with sections of
silicone tube.
Cut ~5 mm sections of tube, then cut then in one side in the length, forming a "C".
This "C" fit over in PCB border under buttons cap, now they don't stuck anymore and their operation is less loud.
I used silicone tube because are available there and I have used this ~14 years ago for similar fix in Thrustmaster F22 PRO trigger.
But any section of soft rubber will do the trick.