Does anyone have any guesses as to what is going on here and the cause? This is occurring on master's mix production blocks from the same cook/noc day with blue oyster spawn from two different dates. (the 3 other species noced aren't displaying this). So far, less than 10% of blocks are displaying this, but may find more.
This is our first run doing master's mix with fresh SD and soy hull pellets. 10-20% of the pellets did not break down completely, even after shaking. The blocks in the very back of the container are getting as hot (the front ones got to 203F inside the bag). My guess is that these blocks got an insufficient cooked and developed it sclerotia from stress from being exposed and battling off contaminants.

That mycelium feels EXTREMELY hard to the touch. And when I broke open the 5lb block, it seemed like it was quite hot, although that could be normal and I just might not have noticed the heat as much before. A lot of exudate coming out of those structures and strong sweet mycelial smell, maybe a little funky, but not too bad. 

Incubation temp ranged from 55-mid seventies.
Substrate ended up being too dry 58-60%
Here is a video: https://photos.app.goo.gl/1eUdRJL5jbZyPGCt7