Having the same issue constantly here. But perhaps I have additional information to help. I work in software support, so I am taking this the same way I would an internal bug, without the extensive back-end knowledge, so apologies for any confusion I have. I just know when our internal cases “sit” without any traction, it is usually because there is not enough information to get started troubleshooting. So maybe I can help 
The Mr and I have the same pc, minus a few upgrades I have made. We typically play D4 together, as we did with D3. We are both playing with cross play enabled as well. He has not seen this error, and I see it probably once every 4-5 hours. We both played through beta’s etc. We are both running the game on a standard SSD drive.
I have noticed this typically happens when I tab out to an additional screen. Perhaps this is where the error lies? Here are the other details that I think make our systems “different” that may help.
Differences in our systems:
My CPU: AMD Ryzen 7 3700X His: AMD 8350FX
My Input devices: Keyboard/Mouse His: PS4 Controller
My 3-Monitor system (Triangle) His: 2-Monitor system (Side by side)
I have also performed all the necessary updates to our systems (minus replacing the dinosaurs, SoonTM.)
-Mini