Yamaha MMP1 Setup Manual page 30

Show the RTB status on MMP1 Editor or MMP1 Controller so that that status is also visible
on the Control Room side. Go to Settings-User Assignable of MMP1 Editor, and create a
button and assign RTB Status to it.
[Create a RTB status button]
Now the status of RTB on both the cough box and MMP1 Editor will interact.
[RTB (Return Talk Back) is ON]
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