[pulseaudio-discuss] combined sink does not work with pulseaudio-dlna

[Ivan Kanis]

Hi Tanu,

February, 16 at 12:50 Tanu Kaskinen wrote:

> On Wed, 2017-02-15 at 17:25 +0100, Ivan Kanis wrote:
>> The author of the dlna plugin has told me that the combined sink feature
>> is not implemented in his module. He has given me an alternative with
>> the loopback module:
>> 
>> load-module module-loopback sink=alsa_output.pci-0000_00_1b.0.analog-stereo
>> 
>> Then pickup the loopback on the Chromecast. It works but, as expected,
>> it is not in sync.
>
> So the source of the loopback is the monitor source of the chromecast sink?

No the source of the loopback is the alsa sound card. I tried to set it
to the Chromecast sink but I got silence then I got a noise that got
louder and louder. I am a little wary to try that again, I don't want to
break anything.

>> I am now looking for a way to delay the local playback but I can't
>> figure out how.
>> 
>> I tried latency_msec=3000 but it set's the latency on the Chromecast.
>
> If the source of the loopback is the monitor source of the chromecast
> sink, increasing the latency of the loopback module should increase the
> latency of what is played to the alsa sink, not the chromecast sink.
>
> It's a known problem that something is wrong in module-loopback related
> to the latency_msec paramter:
> https://bugs.freedesktop.org/show_bug.cgi?id=80770
>
> The loopback patches that Georg Chini submitted recently probably fix
> the latency_msec parameter behaviour.

The latency is working. Before I route the loopback to the Chromecast I
can hear an echo on the local sound card. I need to somehow delay the
local playback but that's where the loopback is being picked up from. A
chicken and egg problem?

I don't think it's worth spending much energy fixing this.

Have a nice evening,

Ivan

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