Noob here: Help with channel change freezing, please (1 Viewer)

neurosis

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Btw MM,
I am willing and able to switch my audio input to the Colossus from the STB to analog (RCA) audio inputs rather than using S/PDIF. I do realize that will also require me re-importing all nearly 300 channels with the new input setting, and probably wipe out my EPG entries, correct? Still willing if that is an easier fix.

Mike
 

mm1352000

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    Mike it does indeed look like I was wrong, and that the Colossus completely stops streaming on channel change. I guess this must be something which is particular to setups involving digital audio (S/PDIF and/or HDMI audio). As previously mentioned, I know that people reported similar problems in the past, but I thought they'd been resolved by Colossus driver updates.

    Unfortunately this issue is not something that I will be able to solve from our side in the short to medium term. In the meantime, reports in the Colossus/HD-PVR support thread do suggest that switching to analog/RCA audio should be an effective workaround. Presumably the difference from the Colossus' perspective is that an analog stream is always present ("not present" is synonymous with silence), whereas the digital audio stream can actually be "not present" [during channel change].

    I'd be really interested to know if simply connecting the analog audio [without changing the channel configuration] has any effect on the situation. If not, you will need to deal with your channels as you said. Considering that you said you're a developer, you may or may not find it simplest to modify the database directly. The following SQL should do the trick:
    Code:
    UPDATE TuningDetail SET audioSource = 5 WHERE channelType = 0;

    [edit: One other thing you might try before editing your channels is to configure the STB to prefer non-DD/AC3 audio. This could make a difference because the Colossus only supports DD/AC3 in pass-through mode. Therefore if the STB is not providing audio (as it probably isn't for a certain amount of time during channel change) then the Colossus may have no choice but to stop streaming... and hence the problem. If the STB chooses non-DD/AC3 audio (eg. AAC or MPEG) then the STB will have to decode to PCM (effectively analog) for output over S/PDIF. On the Colossus side, that audio would be encoded as AAC... and therefore theoretically circumventing the problem.]
     
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    neurosis

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    I"ll try those options, MM. Again, thank you.

    No, I'm not a developer. Not sure how I gave that impression. I'm just a tinkerer with some dangerous programming knowledge in ancient tongues. :D

    Mike
     

    neurosis

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    Good news, MM,

    As soon as I switched my STB to PCM audio output, the channel change failures quit! I didn't have to switch to analog (RCA) inputs.
    I have tried several channel changes without a single video freeze.

    You were correct. The AC3 output was allowing the silence to be deafening to the TV server. :)

    THANK YOU!

    Mike

    P.S. So any idea why my Settings selection in MP does nothing at all? Maybe I somehow accidentally disabled it?

    P.P.S. If I want to add a second STB, what capture and IR control method do you recommend? It would be another IPTV box.
     

    mm1352000

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    Woohoo! :D
    I'm happy to have been able to assist.
    As a favour to me: would you be able to quickly do the test with unmodified channels, STB not set to PCM, and analog/RCA and S/PDIF audio connected. I know it seems crazy, but I'd really appreciate it if you could humour me and try it.

    P.S. So any idea why my Settings selection in MP does nothing at all? Maybe I somehow accidentally disabled it?
    Without log files I can only guess...
    1. Open MediaPortal Configuration.
    2. Go to the plugins section.
    3. Ensure the "settings" plugin (within window plugins group) is enabled.
    P.P.S. If I want to add a second STB, what capture and IR control method do you recommend? It would be another IPTV box.
    For capture...
    If you get an identical Colossus then that would be by far the easiest/safest option. Really - I strongly recommend this.

    If you're thinking of getting a different card...
    Please keep in mind that MP doesn't support "pure" capture cards (ie. cards that don't have a tuner) as a rule. HD-PVR [1] and Colossus [1] are the only exceptions which will work straight out of the box. There's also a patch which adds support for HD-PVR 2 and/or Colossus 2... but that's it. Other capture-only cards won't be detected/recognised.
    Please also keep in mind that if you don't get a Colossus, you will almost certainly have to create a second set of separate channels for the second card. If you get an identical Colossus then you'll be able to reuse your existing channels as is.

    For IR control...
    Unfortunately Hauppauge's IR blaster driver (IRBlast - part of your current solution) has some limitations and quirks. Namely:
    1. It can only control one blaster. Exception: HVR-22** cards, in which case it can only control the two blaster ports on one card.
    2. You can't specify which blaster it chooses to control. This is no problem if there's only one blaster present (as is the case for you now), but it immediately becomes an issue if [for example] you add a second Colossus as I've recommended. Depending on which motherboard slots you use etc. the blaster driver may decide it wants to use the blaster on the new card, and so the existing card's blaster would stop working. Thankfully the driver is somewhat consistent - as long as you don't move the cards to different slots, the driver will always select the same blaster/card. In other words: if/when you add the second Colossus, you may need to move the existing blaster cable from the existing card to the new card.
    All that is to say that if I assume you get another Colossus as recommended, you should be able to continue to use the ServerBlaster plugin to control one STB... but you'll need a completely different solution for the second STB.

    From a MediaPortal TV Server perspective: the solution for the second STB is pretty much going to have to involve IR Server Suite (IRSS). The reason is simple: I'm not aware of any other TV Server plugin which provides blaster support. IRSS is a [free] product [from us - Team MediaPortal] which supports a wide range of IR receivers and blasters. It comes with a plugin for TV Server (TV3 Blaster Plugin) which enables TV Server to use/control any/all of the blasters supported by IRSS.

    So, you'd want to buy a blaster that is supported by IRSS. For that I recommend either a USB-UIRT or a WMC/MCE-compatible transceiver.

    All clear as mud? :)
     

    neurosis

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    No, actually that was very clear and understood. Thanks again for answering all my questions, and indeed, I had accidentally simply disabled the Settings plugin. Turning it back on fixed that problem.

    I also did the experiment you requested. Without modifying the channels input settings I connected the L&R analog audio connectors and switched the STB back to Dolby Digital audio. Once again the channel change video freeze problem returned. Evidently, even though analog audio is present the Colossus is still completely stopping streaming. Is that what you suspected, MM?

    Mike[DOUBLEPOST=1451789205][/DOUBLEPOST]Oh, and interestingly, the PCM audio from my STB is a fairly normal volume level whereas the Dolby Digital required me to turn my systems way up to hear them. Why is the Dolby Digital such a low level signal?

    Mike
     
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    mm1352000

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    Sorry, missed your last reply here. :oops:

    Turning it back on fixed that problem.
    Great. :)

    Is that what you suspected, MM?
    I wasn't sure what to expect. The basis of this request was that I thought I [vaguely, from several years back now] recalled somebody in the Colossus support thread finding that their situation improved when they connected both S/PDIF and analog audio. I guess my memory was wrong in this case. Thanks for indulging me.

    Why is the Dolby Digital such a low level signal?
    I think I'm the wrong guy to ask.

    Perhaps it "appears" that the DD is quieter than it actually is because the DD audio has 5.1 channels but you only have 2 speakers and are not applying down-mixing? (ie. ...you're missing 4 out of 6 channels...)

    ...or maybe it's how it was encoded, because [for example] the movie director wanted it to be that way. My understanding (could be wrong!) is that movie DTS and DD audio is intentionally encoded with wide dynamic range (ie. quiet dialogue can be very quiet and loud explosions can be very loud) in order to be realistic. Lots of AV receivers (and codecs - LAV, AC3Filter) support a feature called "dynamic range compression" which reduces the difference between the quietest quiet and the loudest loud. Such a feature is useful in situations when turning up the volume enough to hear the dialogue properly would result in action scene volume levels that would wake your neighbours and trigger noise complaints.
    https://en.wikipedia.org/wiki/Dynamic_range_compression

    In any case the reason has nothing to do with TV Server. TV Server is just a "dumb pipe" for digital content. Everything just passes on through unaltered.
     

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