[mythtv-users] Fwd: Pixelation/Bad Recordings HDHR Prime -- I am at my wits end

Tue Aug 27 22:02:30 UTC 2013

On Tue, Aug 27, 2013 at 2:56 PM, Captain Hook <captainhookzero at gmail.com>wrote:

>
>
> On Tue, Aug 27, 2013 at 5:51 PM, Chris Porter <hoodlum7 at gmail.com> wrote:
>
>> On Tue, Aug 27, 2013 at 2:30 PM, Captain Hook <captainhookzero at gmail.com>wrote:
>>
>>>
>>>
>>> On Tue, Aug 27, 2013 at 5:22 PM, Chris Porter <hoodlum7 at gmail.com>wrote:
>>>
>>>> On Tue, Aug 27, 2013 at 2:15 PM, Captain Hook <
>>>> captainhookzero at gmail.com> wrote:
>>>>
>>>>> I am not sure how much bandwidth the packet loss test attempted to
>>>>> push.  This issue occurs when there is only a single recording happening,
>>>>> if that makes any difference.
>>>>>
>>>>> Here is a link to a diagram of my network.  Yes, my TrendNET 8 port
>>>>> gigabit switch is just an unmanaged switch.  I have a Sonicwall firewall
>>>>> and a separate Meraki access point (also both connected to the switch).  My
>>>>> frontend has another switch connected (also a TrendNET), but that is
>>>>> upstairs.  For what it's worth, my brand new frontend does act laggy at
>>>>> times with fast forward and loading the recordings screen but this is
>>>>> fairly rare.
>>>>>
>>>>> http://s21.postimg.org/iuqsauaif/Coax_Wiring_Home.jpg
>>>>>
>>>>> The splitter just prior to my HDHR Prime has alternated between
>>>>> Monster Cable splitter, Motorola 2 port signal booster, and a splitter I
>>>>> obtained from Comcast years ago.  All three exhibit this issue.
>>>>>
>>>>>
>>>>> On Tue, Aug 27, 2013 at 5:09 PM, Chris Porter <hoodlum7 at gmail.com>wrote:
>>>>>
>>>>>> On Tue, Aug 27, 2013 at 1:57 PM, Captain Hook <
>>>>>> captainhookzero at gmail.com> wrote:
>>>>>>
>>>>>>> Background
>>>>>>>  I have been having intermittent issues with recording quality with
>>>>>>> my HDHomeRun Prime with Comcast cablecard since the inception of this
>>>>>>> project. I am really remembering why I gave this HTPC nonsense up years
>>>>>>> ago, but I'm already significantly invested in this at this point and I am
>>>>>>> determined to see it through.
>>>>>>>
>>>>>>> Issues
>>>>>>>  Intermittent issues with recordings on MythTV. Some recordings will
>>>>>>> be perfect, others will have pixelation periodically, others will have
>>>>>>> heavy pixelation, yet others will be so bad that the recordings stop during
>>>>>>> playback. The same channel will not behave the same twice--sometimes things
>>>>>>> are fine, other times they are terrible. This seems to happen on any
>>>>>>> channel and do not occur at any particular time of the day or during any
>>>>>>> other operations or recordings on my network.
>>>>>>>
>>>>>>> During playback the pixelation occurs at exactly the same points on
>>>>>>> damaged recordings. This pixelation is also present in other frontends that
>>>>>>> I have used as well as playing them in VLC.
>>>>>>>
>>>>>>> Screenshot of pixelation:
>>>>>>> http://s18.postimg.org/uq2tslkzt/Capture_zpsfb6e2c2a.jpg
>>>>>>>
>>>>>>> Troubleshooting & Attempts at Resolution Thus Far
>>>>>>>  Ran packet loss tests--no packet loss
>>>>>>>  Signal showing 70-100% depending on channel--added Motorola 2 Port
>>>>>>> Signal Booster
>>>>>>>  Signal now showing 100% signal and 100% quality on channels that
>>>>>>> have shown pixelation--issue still occurs
>>>>>>>
>>>>>>> My Setup
>>>>>>>
>>>>>>> Backend Hardware
>>>>>>>  Intel i5 3570k
>>>>>>>  16GB RAM
>>>>>>>  Gigabyte GA-Z77-DS3H
>>>>>>>  Seagate 3TB x 3 (recordings volume)
>>>>>>>  Seagate 350GB (OS volume)
>>>>>>>
>>>>>>> Backend Software
>>>>>>>  VMware ESXi 5.1 (Free version)
>>>>>>>  Ubuntu 12.04 LTS
>>>>>>>  MythTV .26
>>>>>>>  4 vCPU cores
>>>>>>>  12 GB of vRAM
>>>>>>>
>>>>>>> Frontend Software
>>>>>>>  Ubuntu 12.04 LTS
>>>>>>>  MythTV .26
>>>>>>>  (Have both physical machines and VMs with this setup--pixelation
>>>>>>> occurs identically in the affected recordings as well as through VLC)
>>>>>>>
>>>>>>> Any ideas/suggestions would be greatly appreciated.
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> mythtv-users mailing list
>>>>>>> mythtv-users at mythtv.org
>>>>>>> http://www.mythtv.org/mailman/listinfo/mythtv-users
>>>>>>>
>>>>>>>
>>>>>> do you have a splitter any where in the chain to the HDHR Prime?
>>>>>>
>>>>>> --
>>>>>> Working on World Domination since 2001
>>>>>>
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>>>>>>
>>>>>>
>>>>>
>>>>> _______________________________________________
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>>>>>
>>>>>
>>>> If you have access to where your outside splitter is I would look at
>>>> the outputs to see what the dB drop is. It should be listed on the
>>>> splitter. If not you will have to look up the splitter model on line.
>>>> Essentially you would need to add up all the dB drops for all the splitters
>>>> in the chain to your HDHR prime. This chain is most likely the cause of
>>>> poor quality.
>>>>
>>>> what I had to do for my house is get a distribution amplifier which
>>>> provided enough boost to overcome the all my splitters. I then placed this
>>>> amp outside in place of the cable company splitter. In your case, I would
>>>> have the distribution amp in place of "Comcast supplied splitter #1."  The
>>>> goal is to boost the supplied signal before it reaches any of the internal
>>>> house splitters.
>>>>
>>>> --
>>>> Working on World Domination since 2001
>>>>
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>>>> mythtv-users at mythtv.org
>>>> http://www.mythtv.org/mailman/listinfo/mythtv-users
>>>>
>>>>
>>> I have not looked at the splitter on the outside of my house very
>>> closely, but I did look at the one inside the house (Comcast #2) and it
>>> shows -3.5db.  The Monster Cable one I *was* using showed around -7.5db (it
>>> is a 4 way splitter).  I would assume that the outside splitter probably
>>> loses 3.5db as well.
>>>
>>> I don't know how to see the dBmV and dB values for Signal Quality and
>>> Symbol Quality--I only see percentages.  Both show 100% on both Windows and
>>> Mythbuntu.  Signal strength is between 91-95% (without the Moto booster, it
>>> was at 100% with).
>>>
>>>
>>> _______________________________________________
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>>> mythtv-users at mythtv.org
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>>>
>>>
>> Your HDHR Prime has a web interface. If you browse to the IP of your HDHR
>> you will see some status pages. tune a channel and browse through the
>> status page. ( I am at work now otherwise I would look at my HDHR to tell
>> you exactly where to go.)
>>
>> However, lets go with the assumption the comcast splitter outside is
>> -3.5db as well. this means between #1 and #2 you have a -7db signal drop.
>> This does not take into count the splitter for the HDHR and your cable
>> modem. We also do not know what kind of signal as measured in dB or dBmV is
>> comming in to your #1 splitter.
>>
>> the real goal here is to have an amp which negates all the dB drop from
>> your splitters in the house. My strong suggestion to you is to put your amp
>> in place of "Comcast supplied Splitter #1." This way the signal you are
>> getting from Comcast is amplified even more. This should be a good known
>> signal. By good signal I mean positive dB and dBmV values. This is the
>> strong signal from the head end. Since, your diagram shows a two way
>> splitter outside the home your 2 way amp should fit just perfectly.
>>
>> --
>> Working on World Domination since 2001
>>
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>>
>>
> Yes, I see it now, thanks.
> Signal Strength93% (-4.6 dBmV)Signal Quality100% (36.8 dB)Symbol Quality
> 100%
>
> This is with BBC America, a channel I am seeing issues with even after
> installing the signal booster.
>
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>
>
Hmmm, is the signal strength value -4.6dBmv with the booster or without? I
strongly suggest your take my advice about placement of the amp. I am
curious as to the dB signal output of the amp is it 12dB?

-- 
Working on World Domination since 2001
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