Grandson has made up a sound board: https://learn.adafruit.com/adafruit-audio-fx-sound-board with a viscous sounding barking dog and it is triggered with a small motion sensor. For security.

Have connect an old PC speaker but I need something with more volume. Tried a Ultimate Boom speaker and it is ideal but switches off after a period even when connected to the charger.

Any suggestions please?

Many thanks.