This problem is most likely caused by faulty wiring and/or a broken camera. To replace the camera, follow the steps provided in the iFixit repair guide and purchase a new camera part available at online retailers.

If the sound is muffled and/or producing a 'rattling noise', this could be result of speakers that need to be replaced. Replacement speakers can be purchased here.

If your touch screen is not responding, the solution may be as easy as resetting or recalibrating the device. You can find the steps to resetting or recalibrating the device by following these steps.

If your touch screen is not responding the solution may be as easy as resetting or recalibrating the device. You can find the steps to resetting the device or recalibrating it by clicking on the links. If the problem is still occurring the most likely cause is a defective circuit board. You can follow these steps to replacing the circuit board and you’ll be able to find new circuit boards with the following link.