The Yamaha CVP-307 shares manuals with the CVP-309. Manuals are available from Yamaha +++ HERE +++ . You may want to download the user manual and look at pages 196 - 200.

Here is part of what the manual says about local control:
Quote
Turns the Local Control for each part on or off. When Local Control is set to “ON,” the keyboard of the instrument controls its own (local) internal tone generator, allowing the internal voices to be played directly from the keyboard. If you set Local to “OFF,” the keyboard and controllers are internally disconnected from the instrument’s tone generator section so that no sound is output when you play the keyboard or use the controllers.
Notice local control has multiple parts.


Jim Fogle - 2025 BiaB (Build 1128) RB (Build 5) - Ultra+ PAK
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