2015-12-09 0:10 GMT+08:00 Takashi Iwai <tiwai@xxxxxxx>: > Many codecs, typically found on Realtek codecs, have the analog > loopback path merged to the secondary input of the middle of the > output paths. Currently, we don't offer the dynamic switching in such > configuration but let each loopback path mute by itself. > > This should work well in theory, but in reality, we often see that > such a dead loopback path causes some background noises even if all > the elements get muted. Such a problem has been fixed by adding the > quirk accordingly to disable aamix, and it's the right fix, per se. > The only problem is that it's not so trivial to achieve it; user needs > to pass a hint string via patch module option or sysfs. > > This patch gives a bit improvement on the situation: it adds "Loopback > Mixing" control element for such codecs like other codecs (e.g. IDT or > VIA codecs) with the individual loopback paths. User can turn on/off > the loopback path simply via a mixer app. > > For keeping the compatibility, the loopback is still enabled on these > codecs. But user can try to turn it off if experiencing a suspicious > background or click noise on the fly, then build a static fixup later > once after the problem is addressed. > > Other than the addition of the loopback enable/disablement control, > there should be no changes. > How about the amp in at those mixers of surround jacks / mio jacks ? _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
