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Audio (Dolby AC3) problems on FOX?

post #1 of 66
10/16/09 at 5:34am
Thread Starter 
In the last few weeks I've been having problems watching FOX because the audio keeps stuttering constantly. None of the other networks have this problem.

It happens during Fringe, but I know it's not just Fringe because it happens during ads too. I also know it's not just my station, as a torrent I downloaded of the show afterwards has the SAME problem and it was captured from FOX25 in Boston! I'm watching over the air, not cable or satellite.

Is anyone else having issues? It only happens if I listen to the show in 5.1 surround through my receiver; the TV audio plays just fine. Also, if I switch my receiver to "Virtual", instead of DD, it plays fine even though it's still playing the same bitstream.

This is incredibly frustrating as I really enjoy Fringe and hate having to switch to TV audio to enjoy it. I'm thinking it might be an issue with the receiver, but if so, why do none of the other networks exhibit the problem? "Flash Forward" on ABC plays perfectly. Also, when the audio from the receiver mutes and stutters, I can still hear it playing at a very low volume between the bursts of normal volume audio. something is causing the receiver to nearly mute the sound near constantly.

The receiver is a Denon AVR-S1802 connected to the television via toslink.
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post #2 of 66
10/16/09 at 1:00pm
That sounds like the audio problems I've been having with Fox on D*. The first 45 minutes of Hell's Kitchen last week were very nearly unwatchable because it was so bad. Then it pretty much cleared up. That was the worst instance, by far, but it has been happening for the last two weeks or so.
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post #3 of 66
10/16/09 at 3:07pm
Wonder why it is happening in some places, but not others. No problems here in Jacksonville using D* through a Denon 2808 receiver.
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post #4 of 66
10/16/09 at 4:48pm
Thread Starter 
Quote:
Originally Posted by mayest View Post

That sounds like the audio problems I've been having with Fox on D*. The first 45 minutes of Hell's Kitchen last week were very nearly unwatchable because it was so bad. Then it pretty much cleared up. That was the worst instance, by far, but it has been happening for the last two weeks or so.

Does anyone have a contact at FOX we could complain to about this? A contact who actually has a clue? I doubt the typical call-in lines or email addresses will reach the right people.

We need to reach a geek who actually runs the show...
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post #5 of 66
10/16/09 at 7:03pm
Quote:
Originally Posted by petergaryr View Post

Wonder why it is happening in some places, but not others. No problems here in Jacksonville using D* through a Denon 2808 receiver.

same station and no problems
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post #6 of 66
10/17/09 at 10:45am
Thread Starter 
Quote:
Originally Posted by petergaryr View Post

Wonder why it is happening in some places, but not others. No problems here in Jacksonville using D* through a Denon 2808 receiver.

I'm starting to suspect that the bitstream is "damaged" in some way that affects some receivers, but not others.

Even when the audio is cut out I can still hear it at a very low level, which suggests the receiver's "safety mute" has been engaged, to protect the speakers from corrupted AC3 packets.

So something is making the receiver think the packets are corrupted when they're not. Bleah.
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post #7 of 66
10/17/09 at 7:10pm
Same thing here with DTV through a Onkyo TX-SR805 via HDMI on FOX 28 in Columbus Ohio. I watch little on fox, so I just noticed it watching the ALCS last night and tonight. I tried turning off Dolby Digital on the DTV receiver, no luck. If anyone finds anything that works, I hope they post it here. It really sucks, this is the only time of year I can get into baseball.

-John
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post #8 of 66
10/19/09 at 7:53am
Thread Starter 
More details: Only network audio from FOX is affected. Ads played locally (by WSVN-DT 7.1) are not affected and sound fine. So the problem is definitely on the FOX end.

Note that I'm having problems OTA, with an antenna, NOT cable or DirecTV. This is further evidence that the issues are directly caused by FOX and not any other provider.

I sent a comment to FOX explaining the problem, but I kind of doubt it'll get to the right place. That's the pessimist in me speaking. If any of you are having issues, please send complaints as well.
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post #9 of 66
10/19/09 at 12:03pm
i notied the audio cut one twice briefly while watching last weeks fringe. i dont watch fox other than that so i don't know if it happened other than that.

i work in the tv industry, so i can tell you the first place to call is your local fox station. ask to talk to the master control department or the engineer in charge. ask them if they have had any audio problems with their network feed. if so, they can tell you how to get in contact with the national fox company. but i doubt complaining will get you anywhere; if they are having national problems i'm sure they are working on it.
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post #10 of 66
10/29/09 at 6:45am
I live in San Diego and have been having the metallic buzzing and skipping sound problems. I had the same problems when I lived in Madison, WI where Fox told me it was my local affiliate's issue. Then they told me it was DirecTV's fault. When I said I had recently switched from cable because they told me it was my cable company's fault, they stammered over their words and went back to blaming the affiliate.
Well, now I'm in San Diego and am having the exact same issues. Last night was particularly bad - from the 7th inning of the baseball game all the way through the late local news. I switched to SD and although the sound wasn't as brutal, it was crackling and the voices were off by 2 seconds.
I wrote Fox network a pointed email today and copied my Fox affiliate. I am going to call my affiliate today to see if I can get contact info for the appropriate person/group at the network. 4 years is way too long to not have the problem addressed and fixed. Fox obviously does not hold their viewers in high regard. I'm mad as hell and they can kiss my arse.
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post #11 of 66
10/29/09 at 7:02am
I was having the same audio stuttering on Directv watching Fox45 WBFF HD out of Baltimore during the game last night, it was particular bad around the 7th inning as you noted.
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post #12 of 66
10/29/09 at 5:10pm
Called the Fox affiliate in San Diego today and asked for the master control department. The receptionist would not connect me, saying they don't accept calls in that department but if I gave my number they would call back today. They, of course, never called.
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post #13 of 66
10/30/09 at 7:52am
Quote:
Originally Posted by westward ho View Post

Called the Fox affiliate in San Diego today and asked for the master control department. The receptionist would not connect me, saying they don't accept calls in that department but if I gave my number they would call back today. They, of course, never called.

The receptionist was, IMHO, totally correct not to connect you. A live MCR is not a place that calls from the general public should be routed to.

Equally, promising a non-existent call-back is also very poor for viewer relations.

I'd suggest the station engineer would be the person to try to communicate with - either via phone or probably e-mail?
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post #14 of 66
11/1/09 at 9:32am
What I see in New York (WNYW-TV) is a complete stream freeze. Still picture and no audio. Then it just picks up in a few seconds. I don't see an audio-only problem. This is via Comcast cable, but I've never seen it before this year's baseball telecasts. I don't watch a lot of FOX programs otherwise, and I've never seen this on other local broadcasts.

This just in: It happens on football, too.
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post #15 of 66
11/19/09 at 11:27am
I had this Audio Stuttering and out of Synch problem ALL day and night on Fox (Sunday Nov 15th)
Directv San Diego 69/5
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post #16 of 66
1/20/10 at 10:55am
Thread Starter 
Seems this issue is not fixed. I'm still getting audio problems, now when watching "24". This happened on both Sunday and Monday nights.

Is anyone else having issues? I keep wanting to suspect my receiver, but given that FOX is the *ONLY* network that has any problems, and all other AC3 sources play fine, I have to rule my receiver out as being the problem.
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post #17 of 66
1/20/10 at 12:18pm
Fox is also the only one using 448kbit for 5.1 in your area. All other stations appear to be using 384kbit for their audio.
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post #18 of 66
1/20/10 at 5:22pm
hmm, well i dont watch fox too often, but i havent noticed anything in my area. you said you're watching OTA, maybe its just a signal problem...
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post #19 of 66
1/21/10 at 8:28pm
Thread Starter 
Quote:
Originally Posted by coyoteaz View Post

Fox is also the only one using 448kbit for 5.1 in your area. All other stations appear to be using 384kbit for their audio.

Hmm, could older receivers not be compatible with 448kbit AC3? I have a circa 2000 Denon AVR-1802. The thing is like I mentioned a while back, it decodes the stream fine if placed in 5 speaker stereo mode. So it's a mystery.

I really hope I don't have to upgrade my receiver over this. Grr. Is 448kbit AC3 even allowed in the standard?
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post #20 of 66
1/21/10 at 10:58pm
Any DD-compatible receiver should be able to decode up to 640kbit. My circa-1998 Pioneer receiver works fine with 448kbit from Fox (and 640kbit from elsewhere), so I doubt it's an age thing. 448kbit is acceptable under the ATSC A/53 standard, and is used by Fox as well as many station groups using fancy audio processors. Some cable channels use it as well - TNT HD comes to mind.
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post #21 of 66
1/22/10 at 9:56am
Quote:
Originally Posted by zorinlynx View Post

Hmm, could older receivers not be compatible with 448kbit AC3? I have a circa 2000 Denon AVR-1802.
...
I really hope I don't have to upgrade my receiver over this. Grr. Is 448kbit AC3 even allowed in the standard?

No need to growl. Every AC-3 decoder ever made can decode up to 640 kbps (which is the maximum data rate in the AC-3 ssytem.) I think the first consumer box to put out 640 kbps AC-3 was the Xbox in 2001. Yes, 448 kbps is in the DTV standard. ATSC broadcasts can go up to 448 kbps, matching the data rate of (SD) DVDs.

Whatever your problem is, it has nothing to do with the decoder's ability to handle a 448 kbps signal.
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post #22 of 66
1/22/10 at 10:19am
Thread Starter 
Quote:
Originally Posted by hphase View Post

No need to growl. Every AC-3 decoder ever made can decode up to 640 kbps (which is the maximum data rate in the AC-3 ssytem.) I think the first consumer box to put out 640 kbps AC-3 was the Xbox in 2001. Yes, 448 kbps is in the DTV standard. ATSC broadcasts can go up to 448 kbps, matching the data rate of (SD) DVDs.

Whatever your problem is, it has nothing to do with the decoder's ability to handle a 448 kbps signal.

I'm not growling at anyone here, I'm growling at the problem. it's just frustrating, especially since very few people seem to have this problem. (If it were widespread, FOX would have fixed it by now.)

Every other piece of software I analyze the stream with shows it as being valid. Having to drop to Pro Logic to watch my stuff (using analog cables from the TV) is almost a crime when I have a decent sound system!
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post #23 of 66
1/22/10 at 3:10pm
Quote:
Originally Posted by zorinlynx View Post

I'm not growling at anyone here, I'm growling at the problem. it's just frustrating, especially since very few people seem to have this problem. (If it were widespread, FOX would have fixed it by now.)

Every other piece of software I analyze the stream with shows it as being valid. Having to drop to Pro Logic to watch my stuff (using analog cables from the TV) is almost a crime when I have a decent sound system!

It is very widespread. One estimate I saw (from a Fox station engineer) was that one third of all Fox affiliates were having this problem. Most of the reports are from DirecTV or Dish customers where the Fox signal goes through an MPEG-2 to MPEG-4 conversion, and the problems in the digital audio signal cause the encoders to "hiccup" hence the brrrp sound. This is happening in the DirecTV or Dish Local Receive Facility. I assume that the signal you receive at your receiver might look like a good signal with the brrrp sound as part of the audio stream.
In a few extreme cases people with cable and OTA have reported some of these problems also.

I have seen posts saying the problem is something to do with the Motorola splicer at the Fox affiliate that merges network and local HD material. I have also seen posts from Fox station engineers saying that in investigating the problem they have found several issues in their audio processing chain.
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post #24 of 66
1/27/10 at 8:13am
TWC HD box feeding Kenwood VR510 through Monster toslink cable.

All DD 5.1 channels fine EXCEPT for Fox out of Cleveland. Local inserts are fine, but as soon as the network feed comes back I get the horrible stuttering audio. Makes it totally unwatchable.

Contacting the local channel (WJW) is pointless. They don't publish email addresses or phone numbers.

Too bad since 24 and Fringe are among my favorite shows. I have to switch my HD box to PCM and simulated surround.

I'm working with local TWC support to see if their engineering staff can contact the local station.

Todd
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post #25 of 66
2/1/10 at 1:01pm
If I can summarize my efforts on this topic:

Using a Denon AVR-1802 receiver I have the same problem with Comcast in Chicago. In all there are about 10 HD channels (including FOX) where Dolby Digital 5.1 cuts in and out. Switching from Digital Optical to Digital Coaxial does not fix the problem either. I've even tried to run an HDMI cable from my Motorola Comcast box into the TV and then a Digital Optical back to the Denon, still no luck. And yes, standard ProLogic and 5 channel work fine.

I've been researching this for over a year and have concluded that this problem occurs with multiple Services Providers (DirectTV, Comcast, Sky, etc..) and with multiple receivers (Denon, Onkyo, Kenwood, etc..). From what I have been able to gather the problem is actually a fault in the DSP chip used to decode the DD5.1 sound. If I'm not mistaken all of the receivers I have read with this problem all use a variant of the same Crystal DSP chip.

I would be curious to know if any hi-fi experts could shed some light on my theory regarding the DSP chip. If this is the case I would imagine we are all SOL and might as well junk our units. No point in crying to the Networks or Service Providers, they wont listen anyways.
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post #26 of 66
2/1/10 at 1:14pm
I wonder what is going on with the digital stream to do this just on certain channels? NBC, CBS, HBO, and numerous other HD channels all sound fine. Just a handful have this problem.
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post #27 of 66
2/1/10 at 1:24pm
I'm not sure but I can't imagine the problem could persist across multiple Service Providers with non affiliated channels using various stereo receivers. The only link I can find is the DSP chip. I don’t remember my full list of channels that are experiencing this problem but I do know: FOX HD, FX HD, AMC HD, NatGeo HD, and Versus HD all have this problem where I’m at (Comcast in Chicago). Also one other thing to note is that when I watch local sports on FOX HD the sound is fine, no problems.
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post #28 of 66
2/1/10 at 1:39pm
Thread Starter 
Quote:
Originally Posted by bjdouros View Post

From what I have been able to gather the problem is actually a fault in the DSP chip used to decode the DD5.1 sound. If I'm not mistaken all of the receivers I have read with this problem all use a variant of the same Crystal DSP chip.

I have the Denon AVR-1802 as well, so at least this brings some commonality to the problem. However, I wonder how valid your theory about the flaw being in the DSP chip is.

I have had this receiver since 2000 and have played countless AC3 streams from countless sources through it with nary a problem. And now all of a sudden in the past year, I start having issues, and only with FOX?

I think the problem is in whatever software or DSP FOX is using to encode its AC3 streams. The AC3 streams are probably not to spec, but most receivers ignore the problems and play the sound anyway. Our Denons probably have a mute circuit to protect the speakers from noises caused by faulty streams, and the circuit is being triggered by FOX's stream.

Ten years of *flawless* AC3 performance suggests this to be the case. We need to find a way to get FOX's attention on this. Some bad firmware or software out there is causing this, and since it affects so few people, we may indeed be SOL unless we can scream loudly enough.
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post #29 of 66
2/1/10 at 2:04pm
Quote:
Originally Posted by zorinlynx View Post

I think the problem is in whatever software or DSP FOX is using to encode its AC3 streams

My problem is not just with FOX. I really only watch 24 and local sports on FOX. Which is even weirder because I don't have the sound problems with local sports, just 24.

I have the same problem with about 10 other channels though: FOX HD, FX HD, AMC HD, NatGeo HD, and Versus HD are the main ones I watch with the problem. I do agree that this is odd considering I also have had my Denon for almost 10 years with no sound issues to speak of. I am a huge movie fan and love my sound system!! I first noticed this problem a year ago with AMC HD watching Mad Men. I called Comcast and have had technicians out numerous times with no avail. Every time they say it is a receiver issue. Recently Comcast has been adding more and more HD channels and I am seeing it now more and more. Still no issues playing AC-3 with a DVD/Blu-Ray player.
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post #30 of 66
2/1/10 at 2:47pm
Quote:
Originally Posted by zorinlynx View Post

I have the Denon AVR-1802 as well, so at least this brings some commonality to the problem. However, I wonder how valid your theory about the flaw being in the DSP chip is.

I have had this receiver since 2000 and have played countless AC3 streams from countless sources through it with nary a problem. And now all of a sudden in the past year, I start having issues, and only with FOX?

I think the problem is in whatever software or DSP FOX is using to encode its AC3 streams. The AC3 streams are probably not to spec, but most receivers ignore the problems and play the sound anyway. Our Denons probably have a mute circuit to protect the speakers from noises caused by faulty streams, and the circuit is being triggered by FOX's stream.

Ten years of *flawless* AC3 performance suggests this to be the case. We need to find a way to get FOX's attention on this. Some bad firmware or software out there is causing this, and since it affects so few people, we may indeed be SOL unless we can scream loudly enough.

Flaw may be the wrong term. Incompatibility is probably a better way to think about what's happening.
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