Hi Rose Marie,


On the you tube web page, there's a couple of sliders for the player. 
the first one is for moving backward and forward through the file you
are watching, and the second one is the one for increasing and
decreasing the volume. When you land on these sliders, NVDA will go into
browse mode initially but you can tab through the controls until you
find the volume slider and adjust it to your liking. Hope this helps.


Tony