I don't know what re programming the iPad means but you do have system sounds muted. If you have sound in the music app or in Safari videos, but no sounds for notifications, keyboard clicks and in other apps - that is a classic sign that system sounds have been muted. It doesn't necessarily have to be something intentional that you did - a crash may have caused to or updating the device may have triggered it.
If you are sure that it is not the fact that system sounds are muted, have you tried resetting all settings? Settings>General>Reset>Reset all settings. If you do this, you will have to enter all device settings again.
Just in case ......
If you lose sounds for keyboard clicks, games or other apps, email notifications and other notifications, system sounds may have been muted.
System sounds can be muted and controlled two different ways. The screen lock rotation can be controlled in the same manner as well.
Settings>General>Use Side Switch to: Mute System sounds. If this option is selected, the switch on the side of the iPad above the volume rocker will mute system sounds.
If you choose Lock Screen Rotation, then the switch locks the screen. If the screen is locked, you will see a lock icon in the upper right corner next to the battery indicator gauge.
If you have the side switch set to lock screen rotation then the system sound control is in the task bar. Double tap the home button and in the task bar at the bottom, swipe all the way to the right. The speaker icon is all the way to the left. Tap on it and system sounds will return.
If you have the side switch set to mute system sounds, then the screen lock rotation can be accessed via the task bar in the same manner as described above.
This support article from Apple explains how the side switch works.
http://support.apple.com/kb/HT4085