My son has a few toys that are so loud and piercing that they hurt my ears (emergency trucks with sirens, an aeroplane flies around in a circle on an articulated arm, and a toy musical piano). My ears have had almost forty years of abuse, and I find them unbearable; I hate to think of the potential for damage to my son's ears. I don't understand how toys can be made and sold with such deafening noise levels.
I know enough about electricalness to know that I could just open up the toy and snip the wire to the speaker. But what if I don't want to mute it? I have considered covering external speaker grills with tape, but my son would probably just remove the tape. Is there something I can I do – discretely, from inside the toy – to an electronic speaker to quieten it without removing the sound entirely?