KODI 17.1 PVR for TVHEADEND installed but won’t run

I have just installed KODI 17.1 after using version 16 for some time.

My setup is: Ubuntu 16.04 on desktop
KODI 17.1 installed from the Ubuntu software
Backend is tvheadend 4.0.8
PVR is kodi-pvr-tvheadend-hts 3.4.17 This was pre-installed in KODI 17.1

The problem is the PVR wont run. (PVR addons List shows: ” X Tvheadend HTSP Client Adam Sutton, Sam Stenvall…. 3.4.17″)

After configuring it won’t run and It still has an “X” in front of it (no tick)

If I try to rebuild, this, it is the latest version.

I can view TV channels OK in tvheadend itself using VLC and can view videos OK. So its just the TV which wont work.

I have looked in the KODI log (how to attach?) but couldn’t see any relevant error messages.

Any help would be much appreciated.

Richard Templeman