AudioLevelMonitor: do not emit 'level' twice
AudioLevelMonitor: do not emit 'level' twice

pardo-bsso/flask-audio-monitor,fm-futura/flask-audio-monitor,pardo-bsso/flask-audio-monitor,pardo-bsso/flask-audio-monitor,fm-futura/flask-audio-monitor,fm-futura/flask-audio-monitor