Librespot to use MPD as backend

[MRodneyMcKay]

Can you use MPD as the player backend for librespot?
I would like to have MPD as the player for upmpdcli and librespot, so, there would be no fight over who uses the dac.
In the documentation i have read about pipe output fot librespot, but i am not sure on how to use.

Thank you

[GioF71]

Hello, @MRodneyMcKay, no, at least AFAIK, there is no easy way to do that, I think MPD does not generally accept input from a pipe.
But there is an alternative, SpotConnect. With SpotConnect you can create a set "virtual" Spotify Connect players on top of UPnP renderers. So if you already have MPD, you can setup upmpdcli (with UPNPAV mode enabled) and make a UPnP renderer out of it.
Then you can run SpotConnect (UPnP flavour) and you get a Spotify Connect player.

You can setup both upmpdcli and spotconnect using docker using this repo and this other one if you prefer to use docker.

But, back to your consideration:

there would be no fight over who uses the dac

What issue are you experiencing? MPD generally releases alsa devices when not in use, and so does Librespot AFAIK.
Even when using MPD with the solution I suggest, you might still experience some players "fighting" for the same resource, if you (say) have BubbleUPnP open operating on the same mpd instance which would be operated (through upmpdcli) by SpotConnect. OTOH you would have only one application opening the alsa device, maybe that's what you want to achieve.

In the documentation i have read about pipe output fot librespot, but i am not sure on how to use.

You might use the pipe output with SnapCast, but I have never used it until now. Or Owntone as well.

Anyway in case you are looking for bitperfect audio with potentially other services with support for uncompressed audio (and maybe even hi res audio) support, using a pipe output won't probably be the best choice for you.

Let me know if this helps!

[GioF71]

So unless you only have one player on your device

That was my goal with the pipe from librespot to mpd.

understood :-)

About SpotConnect and its port conflict

As far as my baby troubleshppting went, port 1900 is/was the issue, which cannot be modified as the upnp protocol relies on that. Setting up and getting macvlan networking working to communicate with the host was a bit much, so i have decided that i will use librespot :D

I think you're right, I never tried to run SpotConnect on a device where a upmpdcli renderer is running, so I thought the conflict was on port 49152 and that it could be solved.
Can't you try SpotConnect on another device? Maybe your desktop (at least for testing) if your player is another device?

[MRodneyMcKay]

Can't you try SpotConnect on another device?

For testing purposes, i did that, it worked right, but under macvlan it did not. But i don't want to have another PC running just for this (electricity is pricey here in Europe... :/ )

[GioF71]

electricity is pricey here in Europe... :/

Yes... I am aware of that, unfortunately :-)

anyhow, out of curiosity, I tried to start SpotConnect (UPnP) with my image on a Tinkerboard where MPD is running with my new player-launchers and I have upmpdcli running with docker in UPnP-AV mode using my image, and it worked for me, no conflict. I could play from Spotify to my mpd/upmpdcli instance.
Can you share your configurations?

[MRodneyMcKay]

these are my configs.

services:
upmpdcli:
container_name: upmpdcli-renderer
environment:
- UPNPAV=1
- OPENHOME=0
- FRIENDLY_NAME=SMSL SU-8 - Powered by TrueNAS
- RENDERER_MODE=UPNPAV
image: giof71/upmpdcli:latest-renderer
network_mode: host
restart: unless-stopped
user: '0:0'
version: '3.8'

version: "3"
services:
spotconnect-upnp:
image: giof71/spotconnect:latest
container_name: spotconnect-upnp
network_mode: host
environment:
- SPOTCONNECT_MODE=upnp
- PUID=1000
- PGID=1000
restart: unless-stopped

[GioF71]

hello, they look quite similar to my configurations. Can you also post container logs?

[GioF71]

Hello, I was thinking again about the issue with port 1900. I don't think it's SpotConnect conflicting with upmpdcli, because SpotConnect tries to discover UPnP devices, but does not expose itself as one.
Is there any chance that there is another application trying to lock port 1900 on your server?

You might try running upmpdcli on your desktop (you will need to specify MPD_HOST and set it to your server), and verify if this runs properly. That would confirm the hypothesis.

Let me know if this helps

[MRodneyMcKay]

spotconnect.log
upmpdcli.log
mpd.log

Here are all the logs

[MRodneyMcKay]

root@nas[~]# sudo lsof -i -P -n | grep upmpdcli
upmpdcli 152941 Zsolti 3u IPv4 689855 0t0 UDP 127.0.0.1:59633
upmpdcli 152941 Zsolti 4u IPv4 689857 0t0 UDP *:49152
upmpdcli 152941 Zsolti 5u IPv4 689858 0t0 UDP *:1900
upmpdcli 152941 Zsolti 7u IPv4 689859 0t0 TCP *:49152 (LISTEN)
upmpdcli 152941 Zsolti 9u IPv4 689860 0t0 TCP *:49149 (LISTEN)
upmpdcli 152941 Zsolti 10u IPv4 689867 0t0 TCP 127.0.0.1:36504->127.0.0.1:6600 (ESTABLISHED)
upmpdcli 152941 Zsolti 11u IPv4 692275 0t0 TCP 127.0.0.1:36506->127.0.0.1:6600 (ESTABLISHED)

root@nas[~]# sudo lsof -i -P -n | grep spot
spotupnp- 167639 Zsolti 3u IPv4 778098 0t0 TCP 192.168.1.107:49153 (LISTEN)
spotupnp- 167639 Zsolti 4u IPv4 778099 0t0 UDP 127.0.0.1:45669
spotupnp- 167639 Zsolti 5u IPv4 778100 0t0 UDP *:54068
spotupnp- 167639 Zsolti 6u IPv4 778101 0t0 UDP *:1900

[GioF71]

Found this opened by yourself.
Would you like to try spotconnect via the binaries?
From the logs it seems it's selecting another port but then it cannot bind:

2025-05-17 10:03:35.963616+00:00[10:03:35.963] Start:1236 Binding to 192.168.1.107:49153

...

2025-05-17 10:03:39.300563+00:00recv bind(): Address already in use
2025-05-17 10:03:39.300637+00:00unable to create recv socket

If you can't try the binaries, maybe try:

NETWORK_SELECT=192.168.1.107:49153
or
NETWORK_SELECT=192.168.1.107:49154

and see if this changes something.
It might be an issue with the docker image with your specific configuration, something I might fix or configure correctly, if we can make the binary version work properly on your setup.

[GioF71]

Also, in you issue on the SpotConnect repository, you are using my docker image, the author of SpotConnect will not probably support that situation, it would be better to refer to his binaries alone. Just saying :-)