Problems with NTSC-J copy of virtual on

[Spadon]

Hey everyone.
I recently bought a copy of virtual on for the dreamcast. I needed to buy a japanese version since the game never came out in the EU (plus it was cheaper then the US version).

Problem is that I tried using codebreaker, DC-IE and utopia but I get the same results each time. The game loads perfectly fine, but once the game needs to load a fight, it freezes and nothing happens anymore.

Using a burned back-up does work, but my original does not. Does anyone have any tips on how I could possibly fix this (except buying a japanese console...)?