Hi Daisy, pity about that warranty. That Mr. Sod can be a real sod If the Rambler's advice has not fixed it, this may help, not sure.
A) Settings>General>Sounds... Is the Sound slider on?
B) Do a system reset, which iPad recommends should be done periodically, to clean up RAM etc., like this (sorry if you already tried)
Simultaneously hold down both the On/Off and Home buttons until the screen blacks out. Keep holding both, ignore any On slider, until the Apple logo appears. Then let both buttons go and wait, could be a while, until your wallpaper appears, then slide to On.
Hoping that helps
Andrew
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