Has anyone come across a Quinetic wireless controller turning on of its own accord i.e without its paired switch being pressed?

I haven't, and it seems very unlikely, but I have a customer who is convinced that her external lights (which are controlled by Quinetic wireless controllers) have come on "on their own" 2 or 3 times over a period of a few months, always overnight.

My suspicion is that the lights have been left on unnoticed during the day and then noticed at some point in the night.  That said, they are quite bright and noticeable, to my eye, when on in daylight.

I've checked them out a few times and everything seems ok - thoughts?

Thanks in advance

Graham