I recently have issues with mp4 video files not playing audio. These are rough cuts with video and audio. Files play fine in QT player, but when imported into PPro 2014.2 audio is not playing...no waveform...no sound.
Mac Tower 2010
A screen grab of your sequence settings would be handy. Also, I'm assuming you've checked the sequence settings and sound hasn't somehow been muted or something ...
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