MSI IA-945GC User Manual page 31

Hardware Setup
CD-In Connector: CD_IN1
This connector is provided for external audio input.
GND
L
R
CD_IN1
S/PDIF-Out Connector: JSPD1 (Optional)
This connector is used to connect S/PDIF (Sony & Philips Digital Interconnect Format)
interface for digital audio transmission.
JSPD1
VCC GND
SPDIF
S/PDIF Bracket (Optional)
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