So I did some testing, and not much luck. After having a look over Ivan's repo buildscript, I see it pulls the current version of audacious, not the current version of audacious-plugins (this being what provides the PipeWire interface) -- the whole thing is grabbed from Ubuntu Bionic and updated by a PPA which is obviously not configured perfectly.Not 100% sure but it may be because Pipewire is still optional in Debian 12. There are some libs installed with 12, but PipeWire itself is not the default sound server (unless you're running Gnome3 -- according the the release info). So unless you've explicitly installed PipeWire as a replacement, then it could be the cause. Also could the a dependency thing. I'll know when I get a chance to fire up my Testing (now Trixie) image. Will let you know.
Now Debian 13 (Trixie) (which'd be +/- Ubuntu 25.xx Plucky) is the oldest version I can find that lists libpipewire under dependencies for audacious-plugins. Before I bore you with the details, let me just sum it up as this: there's just too much interplay between the newer C and C++ libraries and dpendencies between Debian 12 and 13, and I simply don't have the time or energy to hunt down each issue and fix it bit by bit, since I have family, work, and my own projects going on.
I tried writing my own recipes for Audacious, but that ended with a glibc error which shouldn't have happened since I required the latest libc6 & co. packages. I had plenty success with other apps (I even finally got BlueGriffon), so I'm not sure if this is an Audacious quirk. I even dove into the original AppImage (the one I built from Ivan's script) and tried to modify it but everything is just too finicky.
Worth noting...
- PipeWire isn't default on Debian 12, except for Gnome3 Desktop (apparently). It's basically optional. So you won't benefit from PipeWire output unless you've installed it exclusively, and even then, for merely listening to music, there's not real gain outside of supposed better bluetooth.
- The current AppImage I provided will work with PipeWire, just not directly via PipeWire but rather via Pulse or whatever (currently that's what most things like Mplayer/MPV, etc. do anyway). On the Gnome3 subject, compatibility still fully exists for Pulse AFAIK (I don't really much fancy Gnome TBH).
- PipeWire should be the default on Debian 13 (Trixie), and I say "should" based on Debian's typical adoption cycle, just as I say 13 is about six months off release based of its release cycle.
- So, if you can hang in there for six months, you'll be able to natively get it direct from your repo. You can always keep hacking away in the meantime.
- That all said, to reiterate what others have said: Do you need the latest for anything in particular, because if it's not critical, I would say there's already a defecit ROI in the time you've put into this.
Anyway, I'm sorry things didn't go smoothly for PipeWire support, and I'm not saying this isn't still on my to-do list, it's just somewhere near item 99. As I mentioned, I have personal responsibilities, I go back to work soon, and I have a novel that I really have to get out there, not coz I think it'll make me money -- it won't -- but because it's something I'm passionate about. So, if I get a useable AppImage built, I'll post again in this thread -- but I do emphasize 'if'. In the meantime, I wish you the best of luck getting it up and running your end. I'm happy to still give you advice if you want to build from source or something.