[PROBLEM] Airplay with Fixed Volume

[insaneshow]

Hello All!

Thanks in advance for any help, I've been doing some googling and haven't had any luck.

My setup:
Raspberry Pi 4 - Running latest version of moOde
Yamaha RX-V377 AV Reciever
Pi and AVR are connected via HDMI

My use-case:
The AVR is connected to a HDTV and is typically used when we are watching TV.  Typically we use an AppleTV, but it is connected straight to the HDTV as the AVR doesn't support 4K and/or HDR.  ARC then brings the audio down to our AVR (it's a 2.1 setup, so LPCM is perfect).

There are times where the wife and I would like to have the TV turned off and listen to music.  I set up moOde on a Pi so that we could have an Airplay client connected directly into the AVR, allowing us to turn off the TV.  Woohoo, problem solved and with stuff we already have!

My question:
Whenever we connect to the Airplay client on the moOde, it defaults to a low volume.  So typically I open up Plexamp, connect to Moode Airplay, hit play, and lock my phone.  Then when I can't hear anything, I need to open my phone, turn up the volume on the iPhone, and then adjust the AVR.

I had assumed that setting the MPD Volume Mixer to Fixed would resolve this problem, but so far no luck.  I see that there are some config options in /etc/shairport-sync.conf, but fiddling with those options didn't cause any change.

Any tips on configuring moOde to support a fixed Airplay volume, delegating volume control to the AVR?

Side Question - How does moOde run on a Pi Zero W?  I would love to reduce the footprint

Thanks!!