They are connected to the front of my PC with a Jack Plug, and they have never failed to play when I'm watching a downloaded movie.
However, (they are working OK at the present) over the last few months, on Facebook, they have failed to work, more often than not.
They were working Thursday/Friday but not Saturday and this morning. From about 4pm they have been working.
My download speed is a fairly constant at between 45 to 52mbps, so it's not that.
It's not critical but I'd love to cure the problem.
My guess that it's something Facebook related