Tvheadend

Hi guys,
I'm using Jessie on a RasPi with tvheadend 4.1.
Mounted the RasPi there is a WD PiDrive.

I figured out that when I create recordings (no matter if its via LibeElec or the tvheadend web-interface), those recordings get lost as soon as I do a reboot. They dont remain in the recordings list hence there will be no recording.

Any idea how to fix that?

Cheers
Sylvan