Hollyland Solidcom C1 Pro User Manual page 41

Web Configuration
If you want to assign another group to the headset, click another gray square,
and it will light up and generate an uppercase letter B, corresponding to the B
button on the headset. After completing the group assignment, click Apply.
Note:
4-Wire IN/OUT and UAC IN/OUT support a maximum of four groups, as shown in
the diagram below.
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