You could also have a look here:
https://tvheadend.org/issues/1986
I'm not sure if the code for iptv allows 'PMT monitoring' but you could defiantly try to check it's off.
Looks like there are some know issues though that adam is aware of.
Adam's point in the thread is spot on:-
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Updated by Adam Sutton about 1 month ago
Comment
The problem is that there are CC errors in the stream, a CC error in simple terms means "something went missing". Basically each packet carries a 4 bit counter (unique to the PID), if you get a packet with a CC which is not exactly +1 from the last, then you've missed something and got a continuity error.
Now this can happen for several reasons, but the most common are:
1. Intentional errors. This is rare, but not unheard of for some DVB broadcasters to insert intentional errors to try and trip up unofficial receivers (though it should at worst cause unnecessary error reports, not real damage).
2. Lost in transit, due to errors etc... (i.e. receiver hardware never received the packet)
3. Lost in transfer, i.e. packet arrived, but was lost from buffers before it was passed to application (usually implies application running slowly, and my original thoughts on this issue).
4. Lost in processing, it got to the application but then mysteriously disappeared (i.e. a bug in the processing logic).
I'm ignoring 1 assuming its a non-issue. 1 is difficult to disprove, however your dump file which was generated with a completely different application shows CC errors (so I can only surmise that some genuine, transit, errors are occurring, though odd no transport errors are reported).
3 is really difficult to test without real systems on which the problems occur, however I've done quite a bit to improve this so I really hope this is gone. But you could check very latest master and look at the new CC counter field on the stream status page.
4 is probably the most likely source of errors. At the moment I'm not sure packets are going missing as such, but possibly the way in which CC errors are treated is less than ideal.
Adam
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Post your Debug logs.
Phill