Asus Xonar D1 Quick Start Manual page 9

1.5.3 Connecting digital speakers
SPDIF Out
Plug the optical TOSLINK adapter into the S/PDIF-Out port. Then, connect your
decoder's S/PDIF In port to the optical adapter with the TOSLINK optical cable.
1.5.4 Connecting Line-In audio sources
ASUS Xonar D1 Quick start guide
SPDIF Out
Line In
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