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Date: Tue, 15 Sep 2009 14:09:56 +0300
From: Andriy Gapon <avg@icyb.net.ua>
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Cc: Dirk Meyer <dinoex@FreeBSD.org>, Oliver Lehmann <oliver@FreeBSD.org>
Subject: libmad mp3 distortions
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I can reproduce the following on two very different machines: one is older Intel
CPU/chipset, i386 stable/7; the other is newer AMD CPU/chipset, amd64 head.
When I play certain MP3 files with any player that uses libmad for MP3 decoding,
there are some very loud distortions from time to time. Something like what
happens when too strong signal gets clipped.
Examples of the programs: audacious2, mpg321.
On the other hand, mpg123 plays the same files without any quality problems.

I wonder if anybody else sees this too and if, perhaps, this is a known problem.

I can privately share an MP3 file that demonstrates the problem (upon request).
This is what 'file' has to say about it:
Audio file with ID3 version 2.3.0, contains: MPEG ADTS, layer III, v1, 192 kbps,
44.1 kHz, JntStereo

P.S. i am quite surprised, because while googling I've seen that there was a sound
distortion problem with mplayer and in that case they worked around it by
switching to libmad for mp3.

-- 
Andriy Gapon