Tvheadend

Hi,
because i locked myself out from TVH-Server - and some other little issues - i decided to do a clean LibreElec install. So i installed via memory stick, installed "tvheadend" and "tvheadend client" from official libreelec-repo and configured tvh to work with my dvb-s-card. Watching TV works nicely, including timeshift, but i am not able to record anything: planned recording timers (via EPG) are deleted just before the planned start, even instant-recordings do not work. They are either instantly declared as "finished" or "deleted" an no files are available in the recordings-section of kodi. Where should i start to hunt down the problem?

libreelec 8.2.5
TVHeadend 4.2.6-7