Recently my family won electronic talking toy by buying instant coffee "Jacobs 3 in 1". Toy is a little funny but nothing sophisticated. It records load sounds around itself and after a moment plays them back. When playing sounds it is also bouncing its head up and down. It operates using 3 AAA size batteries.
Unfortunately this toy was too loud for my little son. It scared him. I disassembled it and found that audio signal current is limited with series resistor in speaker circuit. Originally there is 3 ohm. Replaced it with 10 ohm. Probably this value could be even more bigger, because sound is still in medium level. But this was first available part I found so it is OK. In picture below green circle shows location of this resistor.
|Inside of hamster|
Resistor helped with sound level, but other problem stays. Hamster moves its head too quickly anyway. I did not start to investigate this problem. It is a silly toy anyway. :)