Well, with Ginyu, he has had a different voice ever since the 1st Budokai game for PS2. It is because Dale Kelly left the show (he was also the narrator before Kyle Hebert) up untill the end of the Cell Saga. Since Dale Kelly was gone, the redub of Season 2 used his replacement voice actor, Brice Armstrong. Brice Armstrong also r-recorded Dale Kelly's Ginyu lines for continuity reasons.
Actually, Maron was originally voiced by Tiffany Volmer (Bulma's voice actress), so it is unclear why they had Leah Clarke redub her.