Those small-round holes in the bottom-piece--abetted by outflow from any furry critters as like to sit nearby and watch you finger things--are easily plugged. (Had they opted for oval? better I think)

Run damp finger along bottom of screen: base yor Alarum! on what it is covered with. A toothbrush is fine, followed by some powerful-Dyson-like sucker, applied to all air orifices (that long slot across top of the plastic back).

Like when you clean up your car ..it just seems to run Happier, if it was found over-due :-)


Carrion ..sometimes it's inanimate.