In case it’s useful to anyone else who doesn’t feel like vibing one themselves, I put together a small Hubitat driver for controlling WiiM volume over the local HTTPS API.
It supports set volume, volume up/down, mute, unmute, and refresh. Tested with a Hubitat C-5 on 2.5.0.159 and a WiiM Ultra on firmware 5.2.818432.
Rule Machine note: use a custom action with the Actuator capability.
Would your driver work with this?
@Pantheon I don’t have one to test but I think it should…it looks like they all share the same API and documentation.
Just a guess, it probably can support at least some commands but actual volume control will likely depend on how you would have it connected to speakers.
For example, some of the Wiim devices have built-in amps, those will definitely control volume when used with passive speakers.
Yeah exactly…the Wiim Ultra that I built this with doesn't have an amp - it feeds audio via optical to a pair of active (amplified) speakers - so I can confirm that volume control works for that use case.
I’d have to imagine the amplified variants and the Wiim speakers would probably work the same as well since the API endpoints for volume are the same.
Where is this driver? Github only has a license and readme files, even in the zip. No sign of any groovy file.
I’m running a Wiim Pro as well as a Wiim Mini. Does this driver (when available) support volume of these individual devices?
Yup, the driver wasn’t there…sorry about that - Codex posted the license and the readme but didn’t bother with the code 
It’s up there on Github now.
I don’t have a Pro or Mini to test with, but I’d imagine that it will work with both since the API documentation appears to be the same for all models.