<p>try putting a valve right after the filesrc</p>

<p>filesrc ! <b>valve</b> ! qtdemux name=demux ! queue ! h264parse ! 
mp4mux name=mux ! filesink demux. ! aacparse ! fakesink</p>

<p>so when you add the new branch to the demux you can open and close the valve.</p>

        
        
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                                ------------------------------
<br/>Gstreamer 1.14.4
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<br/>Windows
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