This is for my aunt's computer.  She out of nowhere has had her sound stop
working in her machine.  We have tried to disconnect and reconnect her
speakers and you hear the crackle like there is sound, but nothing comes
through that should.  Of course it has been rebooted.  Don't ...

when i open up my pc it comes to the first screen, it used to go on to the
next screen but now it stops and doesnt go farther and now a little yellow
box appears at the bottom with a drawing of what looks like a skeleton
key-how do i fix it???