[mythtv-users] LiveTV issues (root caused to cable signals)

MonkeyPet monkeypet at gmail.com
Mon Sep 3 00:53:59 UTC 2012


With 0.26 (Master Head), I tried a few more experiments:
1. LiveTV - Remote frontend, Tune to a TV Channel within a few mins, it
aborts almost immediately with "max buffering exceeded".  Frontend will
crash and needs to be restarted.
2. Recording - Now schedule the same channel, same show and start the
recording.  No remote frontend are viewing the stream. Recording proceeds
with no problems.

I am really doubting that this is a signal issue.  If it was a signal
issue, #2 would behavior exactly like #1 and would be aborted also.  Also a
majority of my recordings are finishing without any issues.  However,
LiveTV would consistently fail and most of the time fail immediately within
the first 5 mins.

Backend log:

2012-09-02 17:16:20.798928 I [6287/28999] ProcessRequest
ringbuffer.cpp:1098 (WaitForAvail) - RingBuf(/export/data/myth
tv/4766_20120903001527.mpg): Waited 0.5 seconds for data
                        to become available... 225236 < 327680
2012-09-02 17:16:21.299115 I [6287/28999] ProcessRequest
ringbuffer.cpp:1098 (WaitForAvail) -
RingBuf(/export/data/mythtv/4766_20120903001527.mpg): Waited 1.0 seconds
for data
                        to become available... 225236 < 3276802012-09-02
17:16:22.299456 I [6287/28999] ProcessRequest ringbuffer.cpp:1098
(WaitForAvail) - RingBuf(/export/data/myth
tv/4766_20120903001527.mpg): Waited 2.0 seconds for data
      to become available... 225236 < 327680
2012-09-02 17:16:27.569263 I [6287/6351] HouseKeeping housekeeper.cpp:221
(RunHouseKeeping) - Running housekeeping thread
2012-09-02 17:17:04.086174 I [6287/6340] TVRecEvent tv_rec.cpp:1043
(HandleStateChange) - TVRec(5): Changing from WatchingLiveTV to None
2012-09-02 17:17:04.105938 E [6287/29068] HDHRStreamHandler
hdhrstreamhandler.cpp:211 (UpdateFilters) - HDHRSH(1313E021-0):
UpdateFilters called in wrong tune mode
2012-09-02 17:17:05.079236 I [6287/6340] TVRecEvent tv_rec.cpp:830
(FinishedRecording) - TVRec(5):
FinishedRecording(4766_2012-09-03T00:15:27Z) damaged recq:<RecordingQuality
overall_score="0" key="4766_2012-09-03T00:15:27Z" countinuity_e
rror_count="0" packet_count="365988">    <Gap start="2012-09-03T00:00:00Z"
end="2012-09-03T00:15:27Z" duration="927" />
    <Gap start="2012-09-03T00:16:14Z" end="2012-09-03T01:00:00Z"
duration="2625" /></RecordingQuality>


Frontend log:

Sep  2 17:16:53  mythlogserver: last message repeated 10 timesSep  2
17:16:53 fa-Macmini mythlogserver: mythfrontend[2949]: N CoreContext myth
player.cpp:2095 (PrebufferEnoughFrames) Player(0): Waited 19896ms for video
buffers AAAAAUUUAAUUAAULAuAUUAUAAUAAAAAP
Sep  2 17:16:53 fa-Macmini mythlogserver: mythfrontend[2949]: E Decoder
avformatdecoder.cpp:4493 (GetFrame) decoding error#012#011#011#011eno:
Unknown error 541478725 (541478725)
Sep  2 17:16:53  mythlogserver: last message repeated 11 timesSep  2
17:16:53 fa-Macmini mythlogserver: mythfrontend[2949]: N CoreContext myth
player.cpp:2095 (PrebufferEnoughFrames) Player(0): Waited 20012ms for video
buffers AAAAAUUUAAUUAAULAuAUUAUAAUAAAAAP
Sep  2 17:16:53 fa-Macmini mythlogserver: mythfrontend[2949]: E CoreContext
mythplayer.cpp:2118 (PrebufferEnoughFrames) Player(0): Waited too long for
decoder t
o fill video buffers. Exiting..Sep  2 17:16:53 fa-Macmini mythlogserver:
mythfrontend[2949]: E Decoder avformatdecoder.cpp:4493 (GetFrame) decoding
error#012#011#011#011eno: Unknown error 541
478725 (541478725)Sep  2 17:16:54 fa-Macmini mythlogserver:
mythfrontend[2949]: I CoreContext tv_p
lay.cpp:2155 (HandleStateChange) TV: Attempting to change from
WatchingLiveTV to None



On Sat, Sep 1, 2012 at 4:02 PM, Monkey Pet <monkeypet at gmail.com> wrote:

>
>
> On Sat, Sep 1, 2012 at 8:40 AM, Monkey Pet <monkeypet at gmail.com> wrote:
>
>>
>>
>> On Sat, Sep 1, 2012 at 6:01 AM, Michael T. Dean <mtdean at thirdcontact.com>wrote:
>>
>>> On 09/01/2012 01:51 AM, Joseph Fry wrote:
>>>
>>>>
>>>>>  After re-cabling:
>>>>>>> (notice the numbers jump)
>>>>>>>
>>>>>>> [me at mythtv libhdhomerun]$ ./hdhomerun_config 1313E021 get
>>>>>>> /tuner0/status
>>>>>>> ch=qam:759000000 lock=qam256 ss=76 snq=82 seq=100 bps=38809216
>>>>>>> pps=994
>>>>>>>
>>>>>> Those numbers, while clearly better, are still rather low.  I
>>>>>> typically
>>>>>> see values in the 90's.  I seem to recall ss=76 indicates a power
>>>>>> level that would normally be out of spec for digital cable (although
>>>>>> it might just work sometimes).
>>>>>>
>>>>>> First thing, plug the hdhr directly into the outlet using a short
>>>>>> piece of
>>>>>> quality coax, and see if the values are more reasonable.  If not, call
>>>>>> your cable company and ask them to make a service call.  They are
>>>>>> responsible for adequate signal levels at the outlet.  If it looks
>>>>>> good
>>>>>> directly plugged into the outlet, it would point the finger towards
>>>>>> your
>>>>>> coax or splitters (or cable amp if you using one).
>>>>>>
>>>>>>  I just don't understand why recording a show works, but LiveTV always
>>>>> fail.  That seems odd to me.
>>>>>
>>>>>
>>>>>  That is odd.  Do you have fast channel switching enabled?
>>>>
>>>
>> It is set to never.
>>
>> I might have spoken too soon about the issue not occurring on recordings.
>>  Myth lies about the recording times of truncated recordings, so it is hard
>> to tell.  I have seen at least one instance of it during a recording.
>>
>> Until i get my signal issues look at by the comcast guys, my mythbox is
>> useless now, I plan to upgrade to 0.26 to see if the behavior changes.
>>
>
> Now everything is running 0.26-head, as expected I see the same issues.  I
> found a better/shorter coax cable and used that instead and my signals are
> getting better.
>
> This low signal  issue might be a good test case for the developers.  It
> leads to strange mythfrontend behaviors for example, you can easily crash
> the frontend by:
> 1. starting liveTV
> 2. then pulling the coax on your HDhomerun box.
> 3. mythfrontend will either crash OR display the max buffering error
>
> I'll file a bug issue for this case.
>
>
>
>
>>
>>
>>>
>>> Use quick tuning
>>>  - Never
>>>  - Live TV only
>>>  - Always
>>> If enabled, MythTV will tune using only the MPEG program number. The
>>> program numbers change more often than DVB or ATSC tuning parameters, so
>>> this is slightly less reliable. This will also inhibit EIT gathering during
>>> Live TV and recording.
>>>
>>> in your Input Connections in mythtv-setup, IIRC.
>>>
>>> Mike
>>>
>>> ______________________________**_________________
>>> mythtv-users mailing list
>>> mythtv-users at mythtv.org
>>> http://www.mythtv.org/mailman/**listinfo/mythtv-users<http://www.mythtv.org/mailman/listinfo/mythtv-users>
>>>
>>
>>
>
> _______________________________________________
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>
>
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