Acer AL2671W Service Manual page 22

The AV2 input support both of S-video and CVBS video inputs. If both of the S-video and CVBS video inputs
are connected with cables, the S-video input take priority but signal quality has problems because you connect
CVBS with S-video at the same time.
The AV3 could be set either input or TV output from TV OSD menu. While it is set to be output, AV3 would
carry CVBS signal and stereo audio out from TV tuner.
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