Puyo Puyo 4 problem

[sonicdragon]

I got puyo puyo 4 and Puyo Puyo Sun. Sun is working fine except sometimes the "sprites" dissapear briefly or flicker in and out. Not enough to cause a real problem. Puyo Puyo 4 however is experiencing real issues. I know the game is playing because I can scroll through menus and "play". It's just I can sort of only hear me do it. All it displays is the background really. They are both Japanese only games. I have tried getting the rom from one other source only to experience the same problem. I just want to know if you think it's a bad rom or if I need some kind of graphics fix. Any suggestion will help. Puyo Puyo is one of my two favorite puzzle sereies and I was really looking forward to this. Oh and this is my first post. I'm sorry if I'm being a bit of a bother.