The Halo control dims after 15 seconds of inactivity. The first tap anywhere on the ring wakes it up — this tap does not trigger any function. Once icons are illuminated, a second tap on a specific icon performs that action. If taps still don't register, try pressing more firmly and directly on the icon center rather than at the edges. Also check that Display Lock is not active — when locked, the Halo and remote are both disabled.