Hollyland Solidcom C1 Pro User Manual page 27

Product Usage
Upgrade through PC
Power on the headset and open the PC software, which can be downloaded
from the official website or other official sources. Connect the headset to
the PC using a USB-A to USB-C cable.
Once connected, the PC software will automatically detect the headset
and display the current firmware version and the available upgrade version.
Click Yes to start the upgrade process.
Note:
The PC software supports multiple instances, allowing you to upgrade multiple
headsets simultaneously.
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