OWC mercury pro elite drives unmounting

[dimme]

I have a OWC mercury pro elite USB 3 enclosure with 2 WD red drives attached to a mini server. It as been running fine for 2 months until yesterday when the drive suddenly unmount in the own. I have not had a chance to reset the pram etc which I will do tonight. But I am looking for any other troubleshooting tips. The mini runs 24/7 does not sleep. It's running the latest OS with the latest updates. Any help is appreciated, Thanks

 

[satcomer]

The Unmount might be the drive itself starting to sleep! Have you look at that part yet?

 

[dimme]

Yes I found that durning a system update the let drives sleep option was turned on. i turned it off and so far all is well.