Transformers: Animated

Sound and Fury (1x10)

:

Megatron creates Soundwave, a robot in the form of a toy robot for Isaac to give to Sari for her birthday. Bulkhead is the only one who finds the toy to be a bad thing and finds out that the toy is evil. Unknown to Sari, the more she uses her key on Soundwave, the more he will evolve into a bigger robot.