A while ago I made this post:

Ubiquiti Dream Router Throughput Issue

I figured it out. My toddler had evidently messed with the router and damaged the RJ45s from router to wired devices.. There was no actual drop in service so didn't even consider the cables themselves.

Changed out the ends and voila - throughput fixed.

Gonna go put on my dunce cap now and sit in the corner.

Edit:

No idea what was causing the wireless devices to have issues as well since the router itself was pulling correct speeds, but hey. It works now. Even upgraded to 750/750.