ICMag with help from Landrace Warden and The Vault is running a NEW contest in November! You can check it here.
Prizes are seeds & forum premium access. Come join in!
If that doesn't work I'd take some pics over to mycotopia or the shroomery and look for guidance, one of those guys will know what to do to get rid of it and how to prevent it in the future
Although they may not have much context on it's harm to plant growth
I've seen these same things before. Even posted about it and no one could come up with an answer. It's been a few years now.
I've actually go some in a 50 gallon compost drum that has had some soil mixed in it. No plants. No roots. Just amended and inoculated soil. The soil has been composting for about 15 months in this drum. Pulled the lid off it a couple weeks back and the entire surface of the soil was covered in these little balls.
I just shrugged and put the lid back on. I still have no clue what they are. I'll get on figuring it out though now that it's a topic others are discussing.