Many thanks for your replies.  In fact it is all now working ok, so I guess it was just a temporary glitch.  Many thanks

Hi Everyone,
I hope someone can help me.  Two problems have developed with my Nexus 7 and I can't seem to resolve either.
1) My alarm has simply stopped sounding.  I can set it as normal and it shows that I have set it, but when the time comes for it to go off, nothing happens! (I do have the sound turned up before you ask).
2) My screen lock no longer works.  Again, as far as I can see it is set up ok in settings.  It shows that the screen should lock after 5 minutes and it also shows that it will require my pin in order to unlock it, but it simply does not lock.
Both these functions have worked ok in the past and as far as I know I have not done anything to stop them working, or done anything to the Nexus to change any settings.  (although who knows, I could have done something unintentionally)!
Anyway, both problems are very frustrating and if anyone can help I should be very grateful.
Trevor