HDMI cable won't work on 8.1.2

hi. My 30 pin to HDMI cable won't work on my apple devices once upgraded to iOS 8.1.2. My iPhone 4s that's still on iOS 7 still works so I know it's not the cable. But my iPad 2 and jail broken 4s are on 8.1.2 and won't display it just says "this accessory is not supported by this iPhone" just wondering if there is anyway to fix this. Anything on cydia I can download to fix this? Thanks