A typical problem of the tiptoy is that its speaker is not completely child proof and after some time the toy becomes mute. This particular toy worked with a headphones normal so my friend decided to try changing a speaker what solved his problem. Here come some pictures he took:
Take batteries out, unscrew four screws.
Take speaker out and desolder it.
Both speakers - the original one and the new not installed yet one.
This is close-up how the speaker is mounted.
You can ensure that the speaker caused a problem by measuring its resistance.
This is measured resistance of the new speaker, close to 8 Ohms is correct.
This is resistance of the damaged speaker. 2.3MOhms is almost open circuit - a speaker is damaged.