Gremlins in the tech stuff

Have you ever noticed how things seem to go wrong in threes?
On Monday I was asked to set up a sound system for a music appreciation group. I always like to have a plan B when I do these things so I took along a lap top “just in case” The music repro part of the system failed to power up, a situation I had not encountered before. No probs I thought the lap top will do and so it did until the last piece of music when silence. Absolutely nothing not a note. We had to shorten the program because knuckle head here never realised there was a mute button. In my defence though the icon and size was very misleading. It took me about half an hour on my own yesterday playing with the software to identify the button when all sweet music filled my room. The sound system music bit is now at the suppliers for repair.
Last night my wife and I wanted to skype with our grandkids in USA. No probs we do it all the time. Switch on, grandkids call, video linked and away we go. We must have done it a hundred times. Last night skype failed to recognise our video camera and hence no pictures being sent. Great pictures from over the pond though. The grandkids thought it was hilarious granddad trying to fix his computer while they were on line. It took about an hour of fiddling before the big blue button for video on which the grandkids had been telling me to find came on and we had contact. I have no idea what I did to get things back to normal. Why it failed I have no idea, is it still working I guess so because the “camera on” light is showing this morning.