Before getting started, please ensure your controller is updated to the latest Firmware and that you are using compatible hardware for audio.
The following troubleshooting issues should be tried if your SCUF Vantage 2 mute functionality isn't correctly working:
Step 1: Wipe all the Audio Touch Bar using a dry cloth (This is the most common cause, if a fingerprint stain is left on the Audio Touch Bar - it can prevent new inputs from being received.)
Step 2: Reset the controller using the Reset button located under the Circle face button. (Click here for video instructions on resetting your controller.)
Step 3: Attempt using a new headset to ensure the issue is not related to the specific headset you are using. The headset will need to be compatible and fully connected to the 3.5mm port.
Step 4: Ensure the headset is not muted by toggling the headset's mute button (if applicable).
Step 5: Long tap the Home button, ensure the mic is not muted. Navigate to Audio Settings in PS home menu - ensure headset is set to all audio.