Here's how to complete a device restore that may help with a blank or frozen screen, apps crashing or freezing, keypad/touchscreen problems, can't hear, device making noises, can't make or receive calls, and device won't sync.
Good to Know:
Follow the step-by-step instructions provided for Use iTunes to restore your iOS device to factory settings.
Allow several minutes for the reset and reboot processes to complete.
If you can't restore your device, try placing it into Recovery Mode.
To set up the device after the restore has completed, refer to Initial Setup Support.