If your participant is on a mobile device (Android or iOS) and they report an error message that their microphone is silent, it may be due to one of the following issues:
They are not speaking loud enough or directly into the microphone: make sure your participant is speaking loudly enough and that the microphone is not too far from their mouth
They are using a headset with an in-line mute switch that has inadvertently been activated: make sure any in-line mute switch or setting is not enabled
They are trying to use a bluetooth headset that is not actually connected to their device: make sure their bluetooth headset is connected to the device they are using for their session
Some other app or service on the device is using the microphone preventing Lookback from accessing their microphone (e.g. Phone app, headphone specific app, etc): Make sure they close out of any other apps trying to access the microphone. If they are using a bluetooth headset that uses a special app to control additional settings, ask them to try disabling/quitting the app or using a different headset
They are trying to use a bluetooth headset that is low on battery or has a bad connection to their device: have them try a different headset, if available
They have muted/lowered sensitivity for their device's microphone in system settings: have them check audio input in their device/system settings and make sure the microphone is not turned down or muted.
If you've determined none of the above apply, try having the participant uninstall the participate app, reboot their device, reinstall the app and try again. If the issue persists, please reach out to support using the chat bubble to your lower right.