New firmware v04.00.00-607 not working

It’s the content scanning indeed the problem.

Look at here for a solution:

http://community.wd.com/t5/WD-My-Cloud/Slow-performance-Firmware-4-00-00-607/m-p/770627#M18646

It talks about scanning on a USB drive, but the processi is the same for the internal contents.