They go away when you get above them. I increased the mesh’s distance field resolution scale to a high number but the artifacts still persist. Is there any setting that could help with this?
Can you post a screenshot of your Distance Field AO visualization and one of the Mesh Distance Field visualization?
Also include any changed settings for Distance Fields changed in your skylight.
Distance Field AO visualization: http://i.imgur.com/w15mCNH.png
How do I view a Mesh Distance Field visualization?
You can enable the Mesh Distance Field view in the same visualization drop-down as Distance Field AO. In the Viewport go to Show > Visualize > Mesh Distance Fields.
For your scene as well to rule out any material issues and see if this is a DFAO issue, can you try using just a simple base color white material for the floor? Also, try disabling DFAO (Show > Lighting Features > Uncheck Distance Field Ambient Occlusion) and post comparison screen shots if needed.