Trouble copying backups with 3 sessions

[98on18s]

I have a problem with a majority of my backup games being 3 sessions long. When I try to convert the games to a cdi with discjuggler so I can make a copy of them, it freezes while writing the second session. I have no problem with the games that are two sessions long, just with the 3 session games. It freezes for a while, then it either says task completed and i get a 1,000 kb image or it says that a "power on reset or bus reset occured". What can I do? Is there something I could change in the settings?? Any help will be appreciated.