Why did they change the voices in Smooth Moves?

[Just a Wario Fan]

All Warioware games before Smooth Moves had the same character voices. But since Smooth Moves came out,
they changed the voices an kept them so in the later games. Especially the voices of Ashley and Mona are dramatically changed. Why? The voice actors are still the same, so that's not the explanation.

 

[Glowsquid]

Touched used the same compression scheme as the GBA installments, while the games onward use clearer samples. They're indeed the same actors - just not filtered through a shitty GBA sound driver : p.