Optoma Optoma TXR774 - Manual (Page 40)

English
40
Setup | Audio
Volume
Press ʉ to decrease the volume of voice.
Press ʇ to increase the volume of voice.
Mute
Toggle the audio on or off.

Off—the speaker volume is turned on.

On–the speaker volume is turned off.
Audio Input
Enter the Audio Input menu. Select the mini Jack/RCA for audio input
source.
User Controls