mp4's without audible sound

[Adam Merrifield]

There are cases where .mp4 files will play without sound in Audience. The sound tracks will be perfectly audible in VLC (for instance) but not in Audience.

The easiest way for me to reproduce this is to record a video and soundtrack, then export an .mp4 from KDEnlive. The result will have inaudible audio as far as Audience is concerned.

Linux adam-T450 4.4.0-62-generic #83-Ubuntu SMP Wed Jan 18 14:10:15 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

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Vendor ID: GenuineIntel
CPU family: 6
Model: 61
Model name: Intel(R) Core(TM) i5-5200U CPU @ 2.20GHz
Stepping: 4
CPU MHz: 2220.796
CPU max MHz: 2700.0000
CPU min MHz: 500.0000
BogoMIPS: 4389.46
Virtualization: VT-x
L1d cache: 32K
L1i cache: 32K
L2 cache: 256K
L3 cache: 3072K
NUMA node0 CPU(s): 0-3
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