Onboard 3.5mm via Spotify Connect low volume

I have deployed two Raspberry Pi 4 64-bit OS. I’ve got them configured and working as multiroom-master and multiroom-slave. I can play via Spotify Connect with absolutely no problems and they sync flawlessly but the volume is incredibly low. I’ve added the variable SOUND_SPOTIFY_DISABLE_NORMALISATION and set the value to 1 (even though the variable simply needs to exist) and still have this issue. alsamixer is showing 98, as is defined in my SOUND_VOLUME variable and is responsive if I change it to other values. Airplay and Bluetooth are disabled, although I have this problem on stock deployment. I’ve tried it both with my PC speakers and my stereo setup and have the issue in both locations. My phone properly increases and decreases volume, but even at max volume it’s moderately loud, at best.

BalenaOS: 2.88.4
Release: 955385a (set to Track latest)
Output method: 3.5mm jack with AUDIO_OUTPUT set to RPI_HEADPHONES


For what it’s worth to anyone else that may be having this issue, I flashed Volumio to the SD card, dropped it in the pi, enabled Spotify Connect and I’m off to the races. No issues at all.