About the audio level indicator:
When [MIC LEVEL] is set to [AUTO] and in the 
mode: the audio level indicator switches on and off with each press of the AUDIO LEVEL button.
[MIC LEVEL] is set to [MANUAL]
M 
Guide (green bar)
The audio level can be changed when the green bar is displayed. We recommend hiding the bar when you have finished adjusting to prevent accidental changes.
When recording in very loud surroundings, the sound may be distorted even though the audio level indicator shows an appropriate level. In this case, set the mode dial to a mode other than AUTO, and activate the microphone attenuator by setting [MIC ATT] under the MENU options to ON. The microphone attenuator can be used also when recording to the memory card.
Turning the audio level all the way down will prevent sound recording.
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