Zoom H6essential Supplementary Manual page 11

Enabling the EXH-6e inputs
INPUT A and INPUT B of the EXH-6e need to be enabled for use.
1.
Press the INPUT A/B buttons.
This will enable that input jack and light the INPUT A/B status indicator.
NOTE
To record sound input from an EXH-6e, the mic capsule track must be enabled on the H6essential itself.
Confirm that the mic capsule track indicator on the H6essential is lit.
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