SOLTEK SL-KT880E-GR Manual page 41

SL-KT880E-GR/RL/R
3. At the "SPDIF & Speaker Configuration", pick the item "6 Channel "
and "Smart 5.1Plus Enable" to activiate 6 channel configuration. Then
close this window to finish configuration.
4. At finishing the Speakers Configuration, you can also click the
"Speaker Test" bar on the screen to test the 6-channel performance.
The figure below is the "Speaker Test" screen with testing instructions
enclosed on it. Follow the instructions to perform the Speakers Test.
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