A way to make her do it quietly.
It is very important to me because the child is sleeping,
every rustle is heard at night, not to mention systematic clicks.
Where does the loud click actually come from?
The source of the click is usually a micro switch, the plastic case enhances this sound.
It is more important to remove the source of the loud click.
How to do this without changing the micro switches?
Focus will only work if your mouse has micro-switches of this type:

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Some pictures and video
My mouse, ready for operation:

Decision:
Reduce the free motion of the moving contact, it is red in the picture.
It is necessary to disassemble the button, and press the top contact to the bottom, it is green in the picture.
1) Clearance must be left.
2) You need to be extremely careful.

Thus, the gap will be smaller, the move will be smaller, as a result, the click will be much quieter.
I even made it barely audible, but this is not very comfortable.
Well, a short video instruction:
I recommend to train on the corpses, before moving on to the living.UPD : Details about the opening of the micro-switch from the tested method, writes
4vanger .
The easiest thing is to push the narrow blade into the slot near the edge on the long side and at the same time pull the cover up. The second option is to slip the blade from the narrow side down and pull up and toward you. This is somewhat more dangerous - the lid may crack.
It is easier to install the micro switch body by turning the mouse upside down, otherwise the white button may fall out and it will be very difficult to find.
Thank.