Platform trend weird spikes

Hi! I am using platform: trend to track when my intercom display turns on. Anyway I am experiencing a weird behaviour.

This is the bnary_sensor:

- platform: trend
  sensors:
    ringing:
      entity_id: sensor.intercom_ldr
      min_gradient: 8
      max_samples: 20
      sample_duration: 60
      device_class: light

And this is a graph tracing illumination from an LDR (in green) and a sensor.gradient derived from gradient attribute in the above binary sensor:

As you may see, I get weird spikes for no apparent change in illumination… Do you have any idea why this happens?

60/20 = 3 This would mean your sampling your sensor every 3 seconds. How often does the sensor itself update?

In theory every second, at least that’s what I set up on espeasy. Could the issue be connected to this?