Crash as soon as usb drive connected

[dubie]

I have two 4tb MyClouds each with its own 4tb WD MyBooks attached for regular safepoint backups. The only way that I have been able to have reliable USB connections and safepoints is by downgrading the firmware to v3

http://community.wd.com/t5/WD-My-Cloud/Easy-method-to-downgrade-to-previous-version-of-the-firmware/m-p/773073/highlight/true#M18956

If you are happy to downgrade, finish this off with a system only restore and check your USB drives for errors on your computer.