No sound with Animate video tutorials

Hi:
I rarely watch video on my computer but recently revisited the Animation video tutorials and now find essentially no audio. If I crank the volume settings to the maximum I barely hear a voice but not loud enough to understand. I randomly tried another YouTube video (First Lady speech) and it worked fine. I tried other players and browsers with the same results: Michelle has a voice but not so in the tutorials. Ditto on my iPad and my wife’s MacBook Pro. So, it’s not an operating system or browser specific problem. Yet, I have found no related complaints on the board about missing audio. So, it seems I am missing something very basic. Anyone have a solution???
Any help would be greatly appreciated!

I wish I could suggest some kind of solution, but all I can say is that I am on a Mac and I have no trouble with the audio on the video tutorials. I also just tested them on my iPad and can hear the audio fine on that as well.