MWBE II shut itself down today during a Time Machine backup

Using my MWBE II as my time machine backup.   Also using it for my itunes drive.

Today when I went to move some photos off my laptop to the drive, I noticed there was no connection.  To my surprise, the drive was powered off.  I manually turned it on and everything seemed fine.   Upon booting up, the light goes up and down normally and shows about half is filled which is correct.  I have abt 1TB used on the 2TB drive.   

However, Time Machine kicked in and then the drive shut itself down again in the middle and I got a Time Machine error.   Any thoughts?   Time to get a RMA?

I would turn off your Time Machine and see if the drive still shuts down. Then see if you can copy/paste some data to the drive. When has been running for a little while, turn Time Machine back on and see if it powers off. I would also make sure that you have the latest firmware update for the drive. You can check for a firmware update by going to the drives configuration page > Advanced Mode > System tab > Update