WD Mybook 8TB Data Back up very slow

Currently the Mybook 8t is using the WD backup software and is trying to backup 5TB of data from a WD 5TB Mybook. So far it is completed 15 % over a 16 hour time frame. Is this normal? I ran WD diagnostic programs that take about 2 minutes and everythink seems to be OK. I called WD and they want me to run their detailed diagnostic which takes several hours. Not sure about running this diagnostic while the back up is still running. Any ideas?

Using 32 gb ram Dell PC machine Windows 10

I’m having the same issue I have been at 38gb for at least 12 hours and the My Book is making noise like its working. Is there any way to speed it up? The Toshiba 1 TB didn’t take this long to download data. I have it in the 3.0 USB and it 389.41gb to back up. Any feedback yet?