The VR controllers built to pair with the Valve Index Headset are seeing widespread reports of a defect since their launch in June. According to Index Controller buyers, the two controllers' joysticks are malfunctioning when the joystick is tilted and pressed like a button. Specifically, if the joystick is fully moved in a cardinal direction, it either requires significant pressure to recognize it's been pressed or won't recognize its been pressed whatsoever. The defect in the Valve Index Controllers will unfortunately not be corrected soon.
A response to a customer frustrated with the defect posted on Reddit provides Valve's perspective on the issue. The defect is known by Valve and is a part of the Valve Index Controller design. According to the customer support agent's response, the controller's thumbstick is only designed to be fully clickable when it's straight up. When tilted, joystick presses may "require more force" and will not necessarily create the sound or feel of a click.
The Valve representative then provided a test for the user so they could figure out whether pressing the joystick is being registered, even if there's no click. In such a case, the VR controller is up to Valve's standards and an RMA may not result in any improvement. Only if customers report that the test is showing that joystick presses aren't being registered when tilted all the way to the edge then Valve is willing to issue a replacement for the controller or controllers.
To show how widespread the issue is, a poll of Valve Index Controller buyers on Reddit shows that only 10 have controllers with joysticks that tilt and click normally. 12% of owners' controllers don't register joystick presses at all. And the remaining 78% report a varying degree of force required to get the button press to register, but no click or feedback.
The Valve Index Controller defect is particularly controversial because it's an important function in certain VR games. Arizona Sun, for example, binds the button to sprinting so that players can run as they move in a specific direction with just the use of the joystick. The button is similarly used in other VR games where the player may need to use it quickly and often. The button press requiring extra force or not triggering at all limits the function or could even put the player at a disadvantage.
For the time being, Valve is at least aware of the defect. No official fix for the Valve Index Controller has yet been confirmed in the future, though VR enthusiasts have some warranty-voiding hacks that have been shown to work. Long-term, Valve could improve the controller's design and issue an updated model eventually, though how soon that would be possible isn't clear.