Tvheadend

With recent TVH (at least 4.0.4, maybe also earlier), many (not all) recordings fail with "time missed". Strange thing is that tvh webui shows that it records fine from desired start until desired end, even a file size for the reording is shown, but in the moment the recording is supposed to end (all fine so far), status goes to "time missed" and recording is marked as failed, file gets deleted.

Two log messages for such a case, where the recording should start at 14:55 and end at 16:05:
2015-06-04 16:05:00.001 subscription: 0001: "DVR: Shopping Queen" unsubscribing from "VOX HD"
2015-06-04 16:05:00.001 dvr: "Shopping Queen" on "VOX HD": End of program: Time missed

Reported recording file size was ~1.7GB @16:00 which is to low for a HD recording of that length. Also strange, that the file size was not growing while I was watching at the recording progress in the web ui...

Very interesting is what you can see on the attached screen shot, taken at approx 16:00. On the "subscription" tab there are 3 subscription. One in "running" state, uninteresting here, this was my kid watching TV. But the remaining two, both started at the same time 15:23 (btw I only have 2 tuners!) are in state "testing", one is the recording and the other one is an epggrab. Are these two have some sort of other interference somehow?

Does file size of 1.7 GB mean that the recording went well from 14:55 until 15:23 and then the epggrap stuff kicked in an "killed" the recording somehow?