If others are unable to hear you in Cluster despite turning on the microphone, please check the following points.
The system’s default device
This is to check that the microphone you are attempting to use is set as the default device for audio input.
Select the device you would like to use as the microphone by going to the start menu, then “Settings” → “System” → “Sound”. If you have toggled these settings while using Cluster, please turn the microphone off and on once to reflect the changes.
Choose the desired microphone for sound input by going to the Apple menu, selecting “System Preferences” → “Sound” → Input.
Your microphone may be muted if the sound still does not come through after selecting the correct input device.
From the start menu, access “Settings” → “System” → “Sound”, and open the sound control panel. You will be able to adjust the volume (including mute on and off) and other microphone properties from the level tab in the record tab.