Thanks for the feedback, but I had actually already tried both options you suggested, and in both cases, the latency was higher. Second, those tests did not use mechanical buttons; they measured the digital latency from the Teensy pin to the USB...
I am using Teensyduino version 1.62 with an XInputHID interface that I extended in usb_desc.c. Basically, everything works, but I'm encountering confusion regarding latency for an 8000Hz gamepad. When I test just my raw button latency using an...