There are 3 places to check the volume for classroom audio
The video player
Confirm the volume is turned all the way up on the player, this could be YouTube, Vimeo, Windows Movie Player, etc. The volume control is usually located near the pause button.
The computer
Confirm that the volume meter is turned up on the computer (local PC or laptop). The volume control is usually located in the bottom right hand corner of the screen, near the time and date.
The Extron/Crestron control panel
Confirm that the volume meter is turned on. The volume control is a black turnable button found on top of the podium/teaching station.