I’ve got more data! Took a while to get this set up, but I recorded the 3.5mm output of the Voice PE and the Chromecast Audio for the same song:
Top: Voice PE
Bottom: Chromecast Audio
Both are at Max Volume with no options configured in Music Assistant. The Voice PE is clipping like mad whereas the Chromecast Audio not only has more headroom but also a lot higher volume!
I read that the RMS is 2V (2.8Vmax peak) for the Chromecast Audio on the AKM 4430 DAC chip.
Not sure about the one used in the Home Assistant Voice PE, but from what I’m seeing, something’s very wrong.