Even if you have tried more than one extension, it is still possible that it is a ROM with some Bug.
Since the ROm is good, searching the forum, you find this topic:
OR, translating with Google translator:
And what is suggested by rockaddicted is:delete the file: /recalbox/share/system/configs/retroarch/retroarchcustom.cfg the latter will be regenerated, so no problem. edit this /recalbox/share/system/configs/retroarch/cores/retroarch-core-options.cfg file, search for pcsx_rearmed and delete all references to it, save and exit.
You can do all this directly from the local network share (or ssh if you are comfortable).