Go watch how annoying this fucking thing is.
My daughter loves the shit out of these duckies, but my sustained sanity requires the ability to turn the sound off on occasion. First step: pull these screws and see what's inside.
When you pull the duckies with the attached string, it compresses this spring and a metal piece closes the circuit between two spots on that PCB.
The wires between the speaker and everything else are wide open, so I decide to just make it an off switch for the speaker. No need to get complicated.
This looks like a nice flat spot for an off button.
Marked a guide hole with a screw so the bit doesn't jump around. My caliper tells me the diameter of my SPST button is 3/8".
Hole drilled, wires stripped, tips soldered.
Installed the button, soldered it into place, then realized I forgot the nut. Soldering iron is having issues, so I just used some gel super glue on the inside to secure the button beyond what the threads will provide.
Reassembled with a bright green off switch! I bet my daughter will even want to turn it off herself.
Quack is wack. Just say no, kids.