[pulseaudio-discuss] [PATCH v3 0/6] Add default volume to ports

[Alexander E. Patrakov]

27.04.2015 16:34, Tanu Kaskinen wrote:
> Here's the third version of the patch set that aims to fix the Aureon
> volume bug[1].
>
> Changes in v3:
>   - Use pa_parse_volume() in pa_config_parse_volume().
>   - Add mute and save_mute fields to
>     pa_sink/source_port_changed_hook_data to make the mute handling
>     symmetric with the volume handling.
>
> David suggested that I could share the volume parsing code also in
> pactl, but that turned out to be difficult with pactl's relative
> volume adjustments, so I didn't want to do that in this patch set, but
> I plan to do that later.
>
> [1] https://bugs.freedesktop.org/show_bug.cgi?id=81777

I have tested the series. It works as described. However, the heuristic 
that decides between 100% and 30% volume default could use some more 
thinking.

On my new Rotel RA-1570 integrated amplifier, it defaulted to 30% 
volume. Also, because the ALSA mixer does not expose any volume controls 
on this card, PulseAudio applied those 30% in software. As this is a 
high-end amplifier (as opposed to the originally-discussed Terratec 
Aureon Dual USB card) and it has a hardware volume knob, I would object 
to this default on my card.

So, maybe it is a good idea to apply the 30% default volume not on all 
analog ports, but only on paths that have a volume control exposed in 
ALSA mixer, plus some explicit exceptions (including the Terratec card)?

Alsa-info here: 
http://www.alsa-project.org/db/?f=45946d2958764b508773255a8ffffb1bf4e41ceb

P.S. PulseAudio also finds a bogus SPDIF output on the Rotel amplifier. 
Maybe we need a whitelist, not a blacklist, here?

-- 
Alexander E. Patrakov