[Pkg-alsa-devel] Bug#998125: libasound2-plugins: Config file for a52 plugin (60-a52-encoder.conf) produces no/garbled sound via optical digital out (S/PDIF)

[Stefan Lange]

On Tue, 2 Nov 2021 10:14:51 +0100 Jens Schmidt <schmidt at iils.de> wrote:
 > Reported upstream as
 > https://github.com/alsa-project/alsa-plugins/issues/38
 >
 >

Thanks for reporting upstream. I'm also experiencing non-working a52
encoding with the libasound2-plugins package shipped with debian
(1.2.5-2). On my system, the plugin outputs a digital 2-channel signal
without any sound instead of the expected 6-channel AC3 encoded stream.
After some researching I found that the main problem is not the
configuration files, but changes in the libavcodec encode API that were
not handled correctly by the a52 plugin. There were multiple commits in
upstream alsa already to fix the issue (see for example here:
https://alsa-project.org/wiki/Changes_v1.2.5.1_v1.2.6 ).

So I assume that the current version (1.2.5) is just broken with respect
to the a52 plugin.

I'm looking forward to a new release of 1.2.6 (or newer) to be included
in debian, which should hopefully fix the issues again. It would be
great if a maintainer could upgrade the debian alsa packages to latest
upstream (see also this request
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1001697 )


Best regards, Stefan