My 3ds XL got a black screen. It was on 4.2 used for the gateway card. It had problems with the speaker ribbon cable which causes a popping sound. What I did was replaced the ribbon cable and now the popping sound is gone. Problem is it does not display anything at all after replacement of ribbon cable. I can access the firmware upgrade page (Up+L+R+A) but I don't want to try updating it since the gateway card only works on 9.2 below. I have a backup of the 4.2 nand. What is my best option? Thanks.