Last OS 0.6-42 upgrade


I have two miners.
One of them 6xAMD RX570 4 gb has been working for a year without any problem. All cards were stable and cool until last OS 0.6-42 upgrade.
As soon as I upgrade, The miner stopped working. I downgraded it back to 0.6-41 and could not get it worked. I downgraded to 0.6-09 and it works perfectly fine. A few days later I tried to upgrade it back to last 0.6-42 and guess what? It stopped working. Downgrade to 0.6-09 it works like a dream.
If any one knows what is the problem with last version of OS 0.6-42??