It senses movement OK but when it’s time to turn the lights off, the lights flash off and back on, at about one flash per second, for about a minute. The rate of flashing slows a little then the lights go off and stay off until the next cycle. When the lights flash, the sensor makes a clicking sound.
The set-up worked fine, i.e. without the flashing, since the house was new (four years ago) but started this a few months ago.
Would appreciate advice and comments on what might be the cause of this behaviour - could be the sensor is faulty or failing? LEDs not playing nice with an OK sensor?