CAKEWALK UM-3G Owner's Manual page 45

Appendices
CAUTION
Don't make connections like the following.
UM-3G set to SLAVE and connected to a computer
Set to Set to
SLAVE. MASTER.
First unit
UM-3G (or UM-3EX) set to MASTER and connected to a UM-3G/UM-3EX connector
Set to Set to
MASTER. SLAVE.
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