Hello Jacob,  I have a similar box, "Music In Motion", with Christmas
songs from "Mr. Christmas".  It had a 120-volt AC to 3-volt DC adapter.
Here we have 220 VAC electric power.  I use an adapter with an output
of 3 volts DC or 4.5 volts DC.  If I choose the 3-volt DC output it is
a little bit too slow; if I choose the 4.5-volt output it's a little
bit too quick.  3.5 volt should be the best in my case.  Try it with
an adapter instead of a battery.

Kind regards

Hauke Marxsen (Germany)