3DS blue light turns on then speakers pop

Been trying to troubleshoot a hardware issue. 3DS turns on briefly with a blue light, the backlight on the top screen flashes and the speakers pop. This has been happening for a while, but I only recently opened up my 3ds to see if there's any apparent damage. Battery was swollen, so I replaced that, but that didn't fix anything. Ribbon cables are intact and firmly connected. Problem isn't affected by how open the lid is (flat, half open, nearly closed) so it doesn't seem like a connectivity issue. I briefly disconnected the cables from their ports to clean them as a last ditch, but nothing. Literally any ideas would be much appreciated. Hoping I don't have to replace a screen. Pics of motherboard attached.