Plex updated on Echo Show 15, tons of buffering now

I realize this isn't a common issue since using Plex to get around no Echo Show 15 app is a niche usage, however this last round has rendered it unusable for me. I just use it as background in my home office over wifi, unfortunately my primary desktop sits next to it hitting the same mesh node a TCL WB10800 setup.
I've tried having the desktop on the MLO channel and the Echo on normal channel but they still seem to stumble.

Are there any other Echo show 15 solutions I should be looking into? I'm about to move back to the desktop PC hooking into the access point by RJ 45 and then the Echo show on wifi to see if that may be the issue.

It's not urgent, but I'd like to solve this.