Time machine takes very long time to write the back up.
For writing 2,33 GB (from 26,33GB) it takes abou14 hours and I don't know, why it is so very slow. I work with USB 3.0 2 TB external hard disk drive.
Try Here > http://pondini.org/TM/D2.html
From Here > http://pondini.org/TM/Troubleshooting.html
Retrieving data ...