If you're trying to TTI DLC/HDLC items that would explain the freezing. Unless you have either wifi-ed a few times to become exposed the said items or used ez_dlc_install. If that is not the case try checking in actoolkit to see if you have an invalid item. When that happened to me in the past the hex that was freezing me was 0000.
That is only accurate for the downloadable content items...