After automatic update pvr streaming from tvheadend got stuttering after 1 minute. it doesnt happen on movies stream.
The TV on which my TV Box with CoreELEC is installed is very old and goes crazy with some TV streams if I enable Audio passthrough, so I have Audio passthrough disabled.
Can this be your problem?
Im having the exactly same problem on both KI and KIII Pro. After about 1 minute it starts the stuttering. and its not on all channels.