[mythtv-users] HDHomeRun Zero Byte Recording but work fine through HDHomeRun GUI

[David Whyte]

Hi,

My mythTV setup includes a couple of HDHomeRun tuners.  They are
generally flawless in their operation, providing all channels and
never skipping a beat...until recently.

A couple of weeks ago, I applied all security updates to my BE,
including a mythbuntu packaged mythTV update and a new kernel and did
a reboot.  Everything seemed fine until I noticed later that week that
all of the subsequent recordings resulted in a zero byte file.  I
checked the tuners were working, using the HDHomeRun Config GUI tool
and viewing streams on all of the tuners.  I applied a further mythTV
update (not requiring a reboot) and everything came good.  Despite
Google, trac and mailing list searches turning up nothing, I blamed
the bug on mythTV and decided it had been resolved in the second
update.

Last night I also did a hardware upgrade to the BE machine, requiring
it to be shutdown.  Since it was being shutdown, I decided to apply
all new updates, including a new kernel, but elected *not* to update
the mythTV packages from mythbuntu.  Afterwards, I noticed that some
of the nights recordings from just one of the HDHomeRuns had resulted
in zero byte files.  A quick look at the HDHome Config GUI showed that
all the tuners were capable of tuning and displaying a program.  I
then restarted the backend and it seemed that all tuners were again
working fine.

On both occasions, one (or both) actions of using the HDHomeRun Config
GUI or restarting the BE resulted in everything coming good.

Some pertinent information:
- MythTV is configured to use the HDHomeRun tuners via their device ID.
- My BE is also the DHCP server in the network, and it assigns static
IPs to the HDHomeRuns.  (My modem also acts as a DHCP server and it is
a bit of a race condition as to which DHCP server responds when a DHCP
lease is required though investigations have shown that the BE is much
more likely to respond to DHCP requests).
- The mythbackend logs show the failed recordings with logs similar to
the following (note the HDHomeRun device ID of 1110625E-0):

Sep 10 22:53:51 mythBE1 mythbackend[1545]: I TVRecEvent
tv_rec.cpp:1029 (HandleStateChange) TVRec(19): Changing from None to
RecordingOnly
Sep 10 22:53:51 mythBE1 mythbackend[1545]: I TVRecEvent
tv_rec.cpp:3495 (TuningCheckForHWChange) TVRec(19): HW Tuner: 19->19
Sep 10 22:53:51 mythBE1 mythbackend[1545]: E TVRecEvent
dtvmultiplex.cpp:325 (ParseTuningParams) DTVMux: ParseTuningParams --
Unknown tuner type = 0xffffffff80000000
Sep 10 22:53:51 mythBE1 mythbackend[1545]: E TVRecEvent
dtvchannel.cpp:308 (SetChannelByString) DTVChan(1110625E-0):
SetChannelByString(2): Failed to initialize multiplex options
Sep 10 22:53:51 mythBE1 mythbackend[1545]: E TVRecEvent
tv_rec.cpp:3681 (TuningFrequency) TVRec(19): Failed to set channel to
2. Reverting to kState_None
Sep 10 22:53:51 mythBE1 mythbackend[1545]: I TVRecEvent
tv_rec.cpp:1029 (HandleStateChange) TVRec(19): Changing from
RecordingOnly to None
Sep 10 22:53:51 mythBE1 mythbackend[1545]: I CoreContext
scheduler.cpp:637 (UpdateRecStatus) Updating status for Lateline on
cardid 19 (Will Record => Recorder Failed)


Does anybody have any ideas as to what is going on here?  Is it
possible mythTV is not correctly finding the HDHomeRun at startup and
never corrects itself?  Or does it find the HDHomeRun somehow, but at
that point in time, the HDHomeRun has been assigned an IP from the
modem and when it gets a subsequent lease from the BE's DHCP server
mythTV's reference to it is wrong?

Thanks in advance,
Whytey