Tvheadend

For a while I was using WebGrab++ thru XMLTV for feeding EPG to several channels. These channels are DVB channels and they provide Over-the-air EPG data. And now I want to use this EPG data instead. The module is EIT: DVB Grabber. I have tried everything possible in the settings without success, these channels are not fed with this data. I have removed these channels from XMLTV feed, I have unset XMLTV from all possible places I can think of, I have also tried to find the place in the filesystem settings where this is set, but I cannot find anything anormal that leads me to a solution.
Right now there many channels using the DVB Grabber without problem, they never were fed with XMLTV, there are few channels fed with XMLTV, also ok, but then there are these few channels that I need to be fed with DVB Grabber, but they are not, I cannot find out how to fix this.
Any help will be much appreciated, TIA!