So turns out there's a bug that explicitly affects MY setup that was introduced in 19.10 :/
The HDMI Ellesmere audio output is auto-selected per-login rather than the line out that I manually set as default in config files.
Only workaround at this point is to disable audio output auto-switching
It exists in focal as well.
Weird part is that I see the other person who has this issue ALSO has a 24-inch Dell monitor
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