Button on back of stick doesn't work and z axis is all wonky

[DarthVader7u]

Hi,
I recently acquired a VKB Gladiator MK1 and have a couple of issues with it.
The button on the spine of the stick doesn't seem to do anything and doesn't come up in the test profile of the configurator when pressed. My z-axis also after calibration seems to be faulty in some way as when it is moved it jumps randomly as if there is some fault with it. I've tried resetting firmware and multiple calibrations but to no avail. I was hoping members of the community could give me a hand with this and anything done is greatly appreciated. Any suggestions of course please put them down below.

[fallout9]

If the button you're talking about is the pinkie button, then it won't show up in the tester because by default it's programmed as a muted subShift button (it's changing the buttons on the grip).
Z axis (the mini-throttle) has to be included in calibration, otherwise would jump up and down as you described.
Could you post a screenshot taken in VKBDevCfg with Profile/Axes/Logical and Physical axes charts?