Having trouble with VOLUME? Check these controls on your PC and Promethean Board to adjust volume:
First, on the left side of the Promethean Board, there is a lit button. A GREEN button indicates your sound is on, RED tells you the sound is muted. Pressing the button will toggle it on/muted. Above this there is a volume knob, and below are tone controls for bass/treble. (On some boards, there's also a white box mounted to the wall behind the board. This box has a black knob that acts as a Master Volume, be sure it's turned up.)
If you still don't have volume, the problem may be at your computer:
Start with the Windows volume control. It's located in the lower right system tray, near the Windows time/date.
It looks like a little speaker, just click to raise/lower.
If the speaker icon is not in the tray, click the ^ arrow to expand hidden tray icons...
There may also be separate volume controls within the program/website you are using:
::: Windows Media Player has a volume control that's independent of your system volume
To the right is the volume slider; clicking the speaker icon will mute/unmute audio from WMP.
::: YouTube has similar volume controls at the bottom left of the video frame:
a volume slider...
If YouTube volume is muted, the speaker will have an "X" beside it.
Clicking the speaker will mute/unmute YouTube audio.
Checking these areas should help you locate any low level or muted controls.