[mythtvnz] Possibly dying tuner card? (or something else?)

[Rob Connolly]

Hi All,

I've been running my Myth setup for nearly 3 years pretty successfully,
but recently I've been running into a lot of problems with failed
recordings. This started out with almost all recordings on the
MediaWorks multiplex failing, but it has since started occasionally on
the other multiplexes too. From looking at the logs this looks like the
adapter is unable to tune and eventually gives up. This appears to be
more likely when another recording is already in progress. I've done a
couple of retunes whilst this has been going on, but they didn't help.

In the last week we have also started to get a lot of interferance on
some recordings. Last night this produced a recording which was
completely unwatchable due to picture degradation and sound blips.

Looking in the log for this recording came up with something
interesting:

Jul  5 19:25:05 laforge  mythbackend[2881]: W DVBRead
dtvrecorder.cpp:1290 (ProcessTSPacket) DTVRec(7): PID 0x3ec
discontinuity detected (( 5+1)%16!= 7) 0.57985%

This message is repeated 42677 times for this recording! Which fits with
the almost constant picture issues. Aside from that myth completed the
recording 'successfully', athough another recording which started later
failed.
 
Since the hardware and software didn't change since this was working,
I'm wondering if this is caused by a slow failure of the TV tuner card,
or some other part of the receiver setup (which consists of maybe 10m of
cable to the antenna and a Kingray amplifier [with phantom power
injected from ground level]). The other option is some real interferance
- there is a ham radio operator in the next street who I've always
suspected.

The relevant details of my system are as follows:

OS: Debian Wheezy with deb-multimedia packages for myth, etc.
Tuner Card: Hauppauge HVR2200
MythTV Version: 0.26.1+fixes20140227-dmo1

I've uploaded the log from last nights recordings at
http://webworxshop.com/~robert/logs/mythbackend.log.20140705. The
recording 'Midsomer Murders' was the corrupted one, whilst the recording
'Knowing' failed to tune.

I'm going to try and do some investigation with tzap later today and I'll
post the results here.

Please let me know what you guys think.

Thanks in advance,

Rob Connolly