Tiles load slowly

Hello! First of all, I want to thank you for your great efforts!
We are working on fast servers and trying to optimize our tile load performance with Cesium. But tiles load slowly, looks blurry at corners and don’t render all on the screen. How can we fix this?

Thanks for your answer.


Is this with your own tiles and server, or do you see this on cesiumjs.org with, say, Bing Maps as well?