Hi Geoff, Johanna's thorough investigations have centred on the iPad side of things. Sorry if you had already thought of it, but have you looked at Sounds from the Skype side? E.g. In Skype look at Tools>Options>Sounds and ferret around there. Have Sounds been muted? Or can you choose a sound type and is it played back? It's just possible you may have to reset Skype settings themselves.
Andrew
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