Fibaro motion sensors continually reports lux updates

Why do my sensors constantly log the current LUX value? This seems to happen from time to time and I've never been able to figure out why. Is this a driver bug?

2018-08-20 17:49:27.951: **info** Hall Motion Sensor 2 illuminance is 56 Lux
2018-08-20 17:49:25.735: **info** Hall Motion Sensor 2 illuminance is 56 Lux
2018-08-20 17:49:23.519: **info** Hall Motion Sensor 2 illuminance is 56 Lux
2018-08-20 17:49:21.304: **info** Hall Motion Sensor 2 illuminance is 56 Lux
2018-08-20 17:49:19.086: **info** Hall Motion Sensor 2 illuminance is 56 Lux
2018-08-20 17:49:16.868: **info** Hall Motion Sensor 2 illuminance is 56 Lux
2018-08-20 17:49:14.652: **info** Hall Motion Sensor 2 illuminance is 56 Lux
2018-08-20 17:49:12.436: **info** Hall Motion Sensor 2 illuminance is 56 Lux
2018-08-20 17:49:11.101: **info** Hall Motion Sensor 2 illuminance is 56 Lux
2018-08-20 17:49:08.002: **info** Hall Motion Sensor 2 illuminance is 56 Lux
2018-08-20 17:49:05.790: **info** Hall Motion Sensor 2 illuminance is 56 Lux

If it's using the Fibaro Motion Sensor driver, change it to the Fibaro Motion Sensor ZW5 driver and see if that makes a difference.