Sorry to dig up old threads, but I also have this issue.
To work around after a boot:
Settings > Add-ons > PVR Clients > DVBLink
Then go to 'Server Address' which appears blank.
When clicked, the original setting appears, go to OK
Confirm Settings
Disable
Enable
Voila, the plugin loads.
This is very annoying, but I guess it is a plugin issue? Why would KODI or the plugin not retain the settings?
