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MPlayer's system-wide configuration dir is

%%PREFIX%%/etc/mplayer

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If seeking in streams causes the playback volume to be reset to
the previous setting (on 8.x or newer system with VPC enabled),
you and you dislike this behaviour, you have two options:
- Use mplayer's -softvol command line option
- Set the sysctl hw.snd.vpc_autoreset to 0
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