Answers.Body: <p>I don't have a definitive answer, but what you're describing sounds like phase inversion on one of the stereo channels. This causes cancellation when heard in mono of anything centered in the mix, as an announcer voice would most likely be. Someone listening in stereo would not hear much if any difference, so I assume you're listening to a mono feed. It's hard to imagine a scenario where a commercial is delivered in a way that would separate the main channels but leave the background sound.</p>
  
  <p>Why only sometimes? Speculating again, there may be one misconfigured server in a group of servers, and playout of any given spot is randomly coming from that server. It's also likely that these are local insertions, since an issue like this would probably be detected quickly at a national level.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-08-27T16:52:38.543Z
Answers.Text: Thanks Jim for the reply! I think you are onto something. **It could be the center channel.** As for the ads being local, I think they are all national. This is not the traditional cable set-up and there does not seem to be any local ads other than on the broadcast channels. I do listen through my Aragon 2ch set-up and there is phasing and depth when I use it streaming films, however, I cannot say that I have checked this on a cable channel for a long time. I will check out if there is a difference I can see between off the back of the Roku or through the T.V. Curious. Cheers!!
Answers.UserDisplayName: closetnoc
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-08-27T08:36:14.927Z
Answers.LastActivityDate: 2016-08-27T08:36:14.927Z
Answers.UserDisplayName: Jim Mack
Body: <p>I am not a video expert. I used to be an audio engineer (like a 1000 years ago) and have done some video editing on my own professional grade editor for giggles but not in the last 10 years.</p>
  
  <p><em>And yet, I am seeing something that makes me curious.</em> So I thought I would finally ask.</p>
  
  <p>I get cable over OTT via a Roku. Periodically, on channels that have minor packet loss, I have noticed that ads will lose any actor voice and the voice over portion of the content. The background and other sounds are there. Just the voices are missing. For example, an ad for a popular insurance company will have all the background sounds, however, the voice of the person in the video and the voice over announcer are gone. This does not happen for shows. It also does this for most any ad periodically and inconsistently. The same insurance ad can show again in the next ad block just fine. One ad can be missing voices, the next ad is fine, then the third ad is missing the voice. This can happen on any channel from time to time and seems to be tied to very minor packet loss. Basically, the channel is working just fine, just very minor periodic packet loss. This may be a hint.</p>
  
  <p><em>Strange huh?</em> Any ideas? It is not really a problem for me, just a curiosity. In fact, it is kind of nice so I am not really complaining.</p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-08-27T06:07:35.467Z
Comments.Text: Is the audio feed multichannel?
Comments.UserDisplayName: Gyan
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-08-27T06:14:00.730Z
Comments.Text: @Mulvya I have no idea. It is a live stream of one of any cable channels via ACC (I assume is the stream protocol) on Roku. Be that as it may, I am sure they are getting this via a satellite as it exists for a market. I am not sure if they are inserting local ads like traditional cable would. It seems that all the ads are national except for the broadcast channels (also streamed) which does not seem to have this problem now that I think about it.
Comments.UserDisplayName: closetnoc
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-08-27T06:18:14.410Z
Comments.Text: @Mulvya BTW- When I say I am not a video expert, I mean I do not know my arse from a podcast. ;-) After school, I started my career as a systems internals engineer (computer) and quickly forgot everything useful. Worse yet, I am retired and a landlord, farmer, antiques dealer. So now I only which end of the shotgun goes where. Cheers!!
Comments.UserDisplayName: closetnoc
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-08-27T23:33:09.197Z
Comments.Text: That definitely sounds like a bad downmix, but I don't know why that would happen intermittently.
Comments.UserDisplayName: Michael Liebman
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-08-27T23:50:29.950Z
Comments.Text: @MichaelLiebman I like the missing center channel idea. It aligns with the facts fairly well. I tried and set the Roku to Stereo versus Auto (there are only two options) just to see. It still happens. Again, this is not a general streaming problem, so I am thinking that it is coming from the cable provider that way and not happening on my end. At least now I am. I ask because it seemed so odd to my old school mind. ;-)
Comments.UserDisplayName: closetnoc
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-08-28T00:04:33.857Z
Comments.Text: Yes, a proper 5.1 mix shouldn't have VO on the L, R, Ls, Rs, or LFE, only on C. An incorrect downmix would just grab L and R, instead of Lt and Rt that should be sent with the commercial to the provider (if the provider is doing the downmix before transmission) or not using a more sophisticated downmix algorithm.
Comments.UserDisplayName: Michael Liebman
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-08-28T00:22:26.833Z
Comments.Text: @MichaelLiebman It all makes sense. What this company really does is take satellite feeds from the channels and resells to cable providers. Along the way, they offer some cable channels via IPTV/OTT up to 200. OTT has been going through growth pains. In the end, home cable and satellite (tether tv) will have to deal with the reality of an untethered world. They offer OTT if you are tethered. They are not getting the new market. Bundles, tethers, paying for useless channels as a means of supporting them, is all changing. For consumers, it is a cost for performance issue.
Comments.UserDisplayName: closetnoc
Tags: <video><streaming>
Title: Voice is dropped in ads on cable channel via OTT
UserDisplayName: closetnoc
ThreadText: # Voice is dropped in ads on cable channel via OTT
  
  (Asked by: username_0 on 2016-08-27)
  
  I am not a video expert. I used to be an audio engineer (like a 1000 years ago) and have done some video editing on my own professional grade editor for giggles but not in the last 10 years.
  
  *And yet, I am seeing something that makes me curious.* So I thought I would finally ask.
  
  I get cable over OTT via a Roku. Periodically, on channels that have minor packet loss, I have noticed that ads will lose any actor voice and the voice over portion of the content. The background and other sounds are there. Just the voices are missing. For example, an ad for a popular insurance company will have all the background sounds, however, the voice of the person in the video and the voice over announcer are gone. This does not happen for shows. It also does this for most any ad periodically and inconsistently. The same insurance ad can show again in the next ad block just fine. One ad can be missing voices, the next ad is fine, then the third ad is missing the voice. This can happen on any channel from time to time and seems to be tied to very minor packet loss. Basically, the channel is working just fine, just very minor periodic packet loss. This may be a hint.
  
  *Strange huh?* Any ideas? It is not really a problem for me, just a curiosity. In fact, it is kind of nice so I am not really complaining.
  
  **Tags:** video, streaming
  
  > **Comments:**
  > **username_1**: Is the audio feed multichannel?  
  > **username_0**: @Mulvya I have no idea. It is a live stream of one of any cable channels via ACC (I assume is the stream protocol) on Roku. Be that as it may, I am sure they are getting this via a satellite as it exists for a market. I am not sure if they are inserting local ads like traditional cable would. It seems that all the ads are national except for the broadcast channels (also streamed) which does not seem to have this problem now that I think about it.  
  > **username_0**: @Mulvya BTW- When I say I am not a video expert, I mean I do not know my arse from a podcast. ;-) After school, I started my career as a systems internals engineer (computer) and quickly forgot everything useful. Worse yet, I am retired and a landlord, farmer, antiques dealer. So now I only which end of the shotgun goes where. Cheers!!  
  > **username_2**: That definitely sounds like a bad downmix, but I don't know why that would happen intermittently.  
  > **username_0**: @username_2 I like the missing center channel idea. It aligns with the facts fairly well. I tried and set the Roku to Stereo versus Auto (there are only two options) just to see. It still happens. Again, this is not a general streaming problem, so I am thinking that it is coming from the cable provider that way and not happening on my end. At least now I am. I ask because it seemed so odd to my old school mind. ;-)  
  > **username_2**: Yes, a proper 5.1 mix shouldn't have VO on the L, R, Ls, Rs, or LFE, only on C. An incorrect downmix would just grab L and R, instead of Lt and Rt that should be sent with the commercial to the provider (if the provider is doing the downmix before transmission) or not using a more sophisticated downmix algorithm.  
  > **username_0**: @username_2 It all makes sense. What this company really does is take satellite feeds from the channels and resells to cable providers. Along the way, they offer some cable channels via IPTV/OTT up to 200. OTT has been going through growth pains. In the end, home cable and satellite (tether tv) will have to deal with the reality of an untethered world. They offer OTT if you are tethered. They are not getting the new market. Bundles, tethers, paying for useless channels as a means of supporting them, is all changing. For consumers, it is a cost for performance issue.  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_3 on 2016-08-27. Score: 1
  
  I don't have a definitive answer, but what you're describing sounds like phase inversion on one of the stereo channels. This causes cancellation when heard in mono of anything centered in the mix, as an announcer voice would most likely be. Someone listening in stereo would not hear much if any difference, so I assume you're listening to a mono feed. It's hard to imagine a scenario where a commercial is delivered in a way that would separate the main channels but leave the background sound.
  
  Why only sometimes? Speculating again, there may be one misconfigured server in a group of servers, and playout of any given spot is randomly coming from that server. It's also likely that these are local insertions, since an issue like this would probably be detected quickly at a national level.
  
  > **Comments:**
  > **username_0**: Thanks Jim for the reply! I think you are onto something. **It could be the center channel.** As for the ads being local, I think they are all national. This is not the traditional cable set-up and there does not seem to be any local ads other than on the broadcast channels. I do listen through my Aragon 2ch set-up and there is phasing and depth when I use it streaming films, however, I cannot say that I have checked this on a cable channel for a long time. I will check out if there is a difference I can see between off the back of the Roku or through the T.V. Curious. Cheers!!  
  
  ---
  
  