DIAGNOSIS This is a Bluetooth pairing interference issue or low remote battery. The remote uses RF and Bluetooth, which can be disrupted by other devices.
FIX Re-pair the remote. Point the remote at the TV. Press and hold the BACK and HOME buttons together for 5 seconds until the pairing icon appears on screen. Follow the prompt. Replace the batteries with new AAA alkalines, even if the current ones show charge. Ensure no large objects block the path to the TV's bottom-right sensor.
IF THAT DIDN'T WORK Disable competing wireless signals. Move any Bluetooth speakers, USB 3.0 devices, wireless routers, or dense metal objects away from the TV and the remote's usual location. These can cause RF interference.
HEADS UP The remote's gyro/pointer requires recalibration if thrown or dropped. Lay the remote flat on a stable surface for 10 seconds. Do not use rechargeable batteries if their voltage is below 1.5V as they can cause lag.