pipewire-pulse does not support remote tunnels

[Jasper]

Pipewire (pipewire-pulse), as a drop in replacement for Pulseaudio, should find tunnelled Pulseadio sinks over a network.

It currently does not.

Resolution is currently removing the `pipewire-pulse` package with the Pulseaudio packages still installed.

ProblemType: Bug
DistroRelease: Ubuntu 22.10
Package: pipewire-pulse (not installed)
ProcVersionSignature: Ubuntu 5.19.0-35.36-generic 5.19.17
Uname: Linux 5.19.0-35-generic x86_64
ApportVersion: 2.23.1-0ubuntu3
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: Unity:Unity7:ubuntu
Date: Sun Feb 26 22:43:57 2023
InstallationDate: Installed on 2021-02-16 (739 days ago)
InstallationMedia: Ubuntu 20.10 "Groovy Gorilla" - Beta amd64 (20201015)
SourcePackage: pipewire
UpgradeStatus: Upgraded to kinetic on 2023-02-21 (4 days ago)

[Jasper (jasper-mackenzie)]

Loading the module `module-zeroconf-discover` enables the discovery and configuration of remote sinks as expected. Loaded as:
```
pactl load-module module-zeroconf-discover
```

This is non-obvious from a user point of view and I suggest that a default configuration is created at a system level to _at least_ discover network audio sources.

Creating the directory `/etc/pipewire/pipewire-pulse.conf.d/` containing the file `50-network-sink-discovery.conf` with the following content:
```
context.modules = [
{ name = libpipewire-module-zeroconf-discover
    args = { }
}
]
```
enables discovery across reboots.

[Jasper (jasper-mackenzie)]

Unfortunately the discovered network audio sink works intermittently:
 * Audio source (such as mplayer) plays audio to pulse (fine)
 * I can see the stream playing in `pavucontrol`
 * I can see the tunneled connection on the server side
 * The first time I play a file there is no audio and underrun/overrun's in the local pipewire-pulse log
 * The next time I play, or advance to the next track the audio works for a time but stops within a minute or so with underrun/overruns in the local pipewire-pulse log

with `journalctl --user -f` showing the following repeated error:

```
...
Mar 06 11:36:55 carbonicus pipewire-pulse[8698]: mod.pulse-tunnel: underflow
Mar 06 11:36:59 carbonicus pipewire-pulse[8698]: mod.pulse-tunnel: 0x559140eb7fa0: overrun write:50333448 filled:4182528 + size:49224 > max:4194304
Mar 06 11:36:59 carbonicus pipewire-pulse[8698]: mod.pulse-tunnel: 0x559140eb7fa0: overrun write:50382672 filled:4231752 + size:49200 > max:4194304
Mar 06 11:36:59 carbonicus pipewire-pulse[8698]: mod.pulse-tunnel: 0x559140eb7fa0: overrun write:50431872 filled:4280952 + size:49200 > max:4194304
Mar 06 11:36:59 carbonicus pipewire-pulse[8698]: mod.pulse-tunnel: 0x559140eb7fa0: overrun write:50481072 filled:4330152 + size:49200 > max:4194304
Mar 06 11:36:59 carbonicus pipewire-pulse[8698]: mod.pulse-tunnel: 0x559140eb7fa0: overrun write:50530272 filled:4379352 + size:49224 > max:4194304
Mar 06 11:36:59 carbonicus pipewire-pulse[8698]: mod.pulse-tunnel: 0x559140eb7fa0: overrun write:50579496 filled:4428576 + size:49200 > max:4194304
...
```

[Jasper (jasper-mackenzie)]

The issue of configuring network sink and source could and should be solved by using `paprefs` or an equivalent. This is how Pulse and Ubuntu users have been used to setting these parameters in the past.
With `pipewire-pulse` the options largely greyed out.

How to proceed, it feels like this bug report is two parts:

1. Pipweire/Pipewire-pulse parity with previous pulse in terms of default behaviour and configuration
2. Pulse tunnel sinks being intermittent.