[pulseaudio-discuss] module-raop-sink problem (and kindly asking for help)

[Linux User #330250]

Hello!


I have an Apple Airport Express (1st version) and wanted to finally use 
its RAOP function in Linux. But I have a couple of problems with it and 
don't know how to get past them... so I thought, I'll ask for help.


Help!


My setup:

1. The Airport Express in the LAN (local, RJ45) and has a static IP 
192.168.1.21.

2. The PC has another static IP 192.168.1.47, it runs Debian testing amd64.

3. The router is running pfSense (current Community Edition), provides a 
DHCP server and is configured with static IP addresses for known devices 
(a list that I manage manually). All of them are also reachable by local 
DNS names, i.e. "airport" is the same as 192.168.1.21.


So, I installed pulseaudio-module-raop on Debian (apt install). I 
followed https://wiki.ubuntuusers.de/PulseAudio/AirTunes/ and also 
installed paprefs.

Using paprefs, I checked "Make discoverable Apple AirTunes sound devices 
available locally". After a reboot I see TWO devices with the DNS name 
of my AirPort Express WLAN router. But none worked.


I checked pactl list modules and found that their IP addresses are 
completely wrong: 169.254.145.142:5000. So I tried to load the modules 
manually. I removed the wrong ones with "pactl unload-module ##" (the 
modules number from the list) and reloaded the module:

pactl load-module module-raop-sink server=airport sink_name=raop.AirPort

(server=192.168.1.21 works just the same)

That worked.

 > Modul #35
 >         Name: module-raop-sink
 >         Argument: server=airport sink_name=raop.AirPort
 >         Usage counter: 1
 >         Properties:
 >                 module.author = "Colin Guthrie"
 >                 module.description = "RAOP Sink"
 >                 module.version = "9.0"

What did not work was to add option 
sink_properties='device.description="AirPort Express"' -- the module 
always failed to load that way. I am also not able to change its name 
later, using:

pacmd update-sink-proplist raop.AirPort device.description="AirPort Express"

only writes "Failed to parse proplist." I also tried module.description, 
which also failed.



Anyway, I can now see the "sink" as an output choice in pacucontrol and 
I can make an application use this output for sound.

This is partly success -- finally I got the module loaded correctly!


Only, the sound doesn't work. I get parts of the sound every 2-4 seconds 
or so, inbetween is silence. The sound piece that comes through is about 
1/3rd of a second long (or less).


I see the same effect both on the output device itself (I hear the sound 
as mentioned: only pieces of it now and then) as well as I see the 
levels likewise in pavocontrol on this output sink. So I assume that the 
problem is in the module, or in the configuration of it or in pulseaudio 
configuration.


My questions:

1. What should I try or what have I done wrong in the first place?

2. Is there a way to get steady sound output to the RAOP device and how 
do I configure this?

3. Is there a way to set the sink statically (without 
module-raop-discover which gets the wrong IP addresses and creates two 
devices with it) and to automatically set this up with the start of 
pulseaudio?


Thanks in advance,

Linux User #330250  aka  Andreas