We have previously found that this can occur when the motion sensor on the mirror/cabinet is experiencing interference from a nearby object.
We do recommend leaving a space of at least 15cm between the sensor and an adjacent wall/object (this does include a shelf, tap, tile trim) to ensure the sensor can work to its full ability and to avoid anything interfering with it. Please check your mirror to ensure that it has been installed correctly.
If your mirror or cabinet does not have a motion sensor or you believe there is more than a 15cm gap between the sensor and any other object, please e-mail us with a video to our support team at firstname.lastname@example.org . The video should capture where the unit has been installed and the unit when a hand is passed underneath the sensor. One of our team will be more than happy to investigate the issue for you.
For more information, please contact us on 01977 522021 Monday - Thursday 8.30am - 17.00pm, Friday 8.00am - 16.00pm or fill out an enquiry form by clicking here.
Pebble Grey Support Team