Yamaha MMP1 Setup Manual page 66

Choose "5.1" as Speaker Format, and click on "Next >"
[Setup Wizard – Sample Rate/Speaker Format Settings]
"5.1" or other multi-channel formats can be selected only when using Setup Wizard. If
chosen in Setup Wizard, speaker-shaped mute buttons are available in the Controller
View of MMP1 Controller.
Even if "L/C/R/Ls/Rs/LFE" or "L/R/Ls/Rs/C/LFE" as the surround channel order is
selected, internal order or the order shown in the Speaker Matrix is always in the order
of "L/R/C/LFE/Ls/Rs" and only the order of input/output patching will be changed.
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