Sony PCG-GRX580P - Manual (Page 73)

To connect a CD player, active speaker, or an amplifier
If you use the port replicator to connect a CD, MiniDisc, or audio cassette player, you may use the LINE IN jacks. To connect
an audio output device to the port replicator, use the LINE OUT jacks. Both sets of jacks consist of one Audio (L) jack and
one Audio (R) jack.
Connecting an Audio Device to the Port Replicator
To connect an audio output device to the notebook, use the AV Out jack and an audio cable (not supplied).
Connecting an Audio Device to the Notebook
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