Question
I asked you about getting rid of these peasts in the house. Perhaps you remember it.

I want to ask you about some devices which are available in market.
These devices are said to produce ultrasonic /sub sonic noise and blasts. It is claimed that these sounds which can not be heard by humans  but are heard by animals and pests like lizzards will drive them away.
Please confirm that geckos are sensitive to ultra-sonic/sub-sonic sound. I mean can the geckos hear these sounds.
Are you aware of the efficacy of such machines
I will be obliged if you can advise me
with best regards
amulya pandit  

Answer
I do remember it.  There is no peer-reviewed evidence that I am aware of that supports the claims of these ultrasonic repellent manufacturers. In fact a lot of study shows most of the animals can't even hear the noise.

Even animal rights protest industry groups, groups who would love to have a so called non-lethal method of controlling wildlife problems don't endorse these products.

Visit http://icwdm.org/ControlMethods/ultrasound.asp  to learn more.   I have not seen research on whether geckos can hear the sound. but even if they did it doesn't mean that it will drive them away. Urban animals hear all kinds of noises. they just adapt the same way we do. I would save your money and spend it on tightening up the building.