Optoma DS550 User Manual page 51

Freeze
Freeze the projected image.
AV mute
Cut off the AV Mute temporarily.
Only pressing AV Mute again can
output sound and image. If any
other buttons are pressed, the
projection image will become
abnormal and no sound will be
output.
S-Video
Display S-Video signal.
VGA
Switch input source to VGA1 or
VGA2 by sequence.
Video
Display video signal.
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