L2 and R2 /buttons 7 and 8 stuck after cleaning

Hi guys, I had a rather trashy looking but fully functional dualshock 4 - so I ordered a new shell, buttons, ribbon cable, etc from ebay to rebuild it. Basically everything is brand new except for the battery, motherboard, and usb board. Upon reassembly the controller works fine in the PS4 menus, but not at all in game, which lead me to suspect a stuck button. I plugged the controller into a windows 7 PC to test it, and in the controller settings *(where you test the joysticks and button assignments) it is saying buttons 7 and 8 are constantly pressed (L2 and R2 triggers) but the triggers respond OK on the analog testing axis. So while it appears the buttons are stuck, they aren't. any ideas? everything in the controller is new - new conductive film, new buttons, new rubber membranes, new shell, etc so I know it isn't a case of a dirty pad or contact. the L2/R2 springs are new as well, and everything feels like it is installed correctly.