Passing volume to OwnTone and end devices?

[owldown]

I've got several AirPlay(1) devices including my Yamaha receiver, and I'd like to be able to send audio from my iPhone to multiples of those devices, which isn't possible as they aren't AirPlay2. I thought maybe I could set up Shairport-sync and Owntone to imitate something like what I want.

In a Proxmox LXC, I was able to install OwnTone and Shairport-sync, and I can play from the iPhone to Shairport, through a fifo pipe, and then Owntone sends the audio to each of the existing AirPlay (1) devices. But now, when I change the volume on the iPhone, it doesn't change the volume sliders in OwnTone, and it no longer changes the volume on my receiver. There are now four volume controls (the phone, the group in OwnTone, and each of the end devices in OwnTone) instead of one, and that's no good.

When AirPlaying from my phone just to the Yamaha receiver, changing the volume on the phone changes the volume on the receiver itself (even when the phone is locked and in my pocket, which is great!), and I'd like to have that convenience when sending audio to multiple devices.

Does anyone know if there is a way for my adjustments of the volume on the source device to be passed through Shairport, through OwnTone, and on to the end device? I'd be willing to set up multiple instances of Shairport and OwnTone, one for each end device, if that would work, but I've not yet figured out the best way to get those volume changes to make it all the way through the chain.

[owldown]

Okay, I feel a little silly now. I worked on a shell script to run on volume change events that would use the OwnTone API to PUT a new volume into Owntone with curl, and then changed the Shairport-sync setting ignore_volume_control = "yes";

I did this to have a single gain stage and not have Shairport attenuate the volume before sending it to the pipe for Owntone, and somehow that also made it so that the volume is "ignore"d by Shairport, but passed along to OwnTone. Exactly what I wanted, with no scripting involved. Hope this helps someone else.