in pro music audio editing you can have it remove all audio below a certain volume. you will then be left with a lot of spaces (i believe).
after which you can easily see the spaces and bring them together. but this is for audio only. you could do it for just the audio track. line it back up in the video editor, look at the wave form and delete the empty waveform areas.
but if you need to do it for audio only – the first thing i mentioned could get you there quite quickly.
