HDMI Sound problems -- my TV or the U-verse STB?

[ShubertAlleyCat]

On my new HDTV (Panasonic) which is connected to a STB (non-DVR) by an HDMI cable, I am having sound issues.  After watching for about an hour, the sound, and this can be on HD and non-HD channels, starts getting "garbled."

I can fix this issue by changing either the STB option from "Stereo" to "Surround Sound" or vice versa.  Or on my TV I can go to the audio output and reset it to Digital.  Both of these fix the problem, but it keeps recurring over and over.

If I don't fix the issue, sometimes it resolves itself after about 10 minutes, but it is a pain in the butt to wait this long!

Is there a particular setting I should have the STB on for HDMI connection?  Or is it an issue with my television?  Perhaps I should scrap the HDMI connection and go another route?

Any thoughts or suggestions would be greatly appreciated.

SAC

[RCSMG ACE - Master]

There are few threads about audio drop outs when using surround sound, but I don't call anyone posting audio gets garbled and being able to correct it with the methods you used.  Check the connections on your equipment, and try doing a soft or hard reboot of the stb.  It also could be related to a handshake issue, but I am guessing.  While the tv and stb are turned on disconnect the hdmi cable from the stb, press and hold the power button until the lights on the stb blink.  After 5 minutes reconnect the hdmi cable to the stb.  Just some thoughts.

[hpmsrm]

I gather from your comments that you are NOT trying to use the Dolby surround sound but, rather, just ordinary stereo.  We are running the same way at our house and, in this case, the proper setting of the STB or DVR would be for stereo sound.......NOT surround sound.  In our case....how the TV set itself is set for audio output has no effect.    Also we have had some comments on this forum that one should make sure that the menu/guide sound effects are turned OFF.    Here in our house....with our big screen Sony HD.....when I tried turning on the surround sound in the DVR...our audio immediately disappeared.  So I just leave it in the stereo position.   We have no interest in surround sound and are not set up to take advantage of it.

[ApexRon]

Okay, time for me to chime in.

First, U-talk really needs an administrator to organize topics, perhaps creating subtopics. Also, ATT needs to have a subtopic of known issues with no replies allowed but just a vote; yes I have the issue or no not my issue (recording individuals contact information for update notification).

Let me summarize my situation. I have the same the same HDMI setup as I have had through a year with the cable companies DVR and a year with a TiVo and have never experienced the symptoms I am now experiencing with the U-Verse Cisco IPN4320.

Surround Sound issues:

1. Intermittent audio drops

2. Intermittent crackled or garbled sound

In each case the issues is resolved by changing the DVR setting to Stereo which is not an acceptable fix.

I have contacted ATT U-Verse support and they have confirmed that a fix is in the works. I have been advised by ATT that the issues are associated with the buffers used for audio in the DVR. ATT also says no ETA on fix rollout. Having been in engineering for 40+ years, I offered my system to be used for field testing. Waiting ... just waiting

[Uniblurb3 ACE - Guru]

ApexRon, looks like a fix to your surround sound problems, and 5.1 audio drops, may be in the works. You can provide your input in the below listed thread/link. Good luck.

http://utalk.att.com/t5/TV-Programming/5-1-Audio-Fix-Implementation-Your-Feedback-Needed/m-p/255899#...

[ApexRon]

The audio drops appear to be resolved with the fix ATT rolled out at the beginning of the week.

However, I am still getting garbled/crackled sound when using Surround Sound on HDMI. The last failure occurred when playing back a recorded show (recorded after the ATT fix was distributed). I immediately changed to stereo and the issue dissappeared.

This weekend I hope to do further testing to determine more exact failure senerios.

[RCSMG ACE - Master]

Have you tried using an optical cable?

[ApexRon]

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RCSMG wrote:

Have you tried using an optical cable?

---

The HDMI cable connection to my Yamaha YSP-4000 has been in use by a Time Warner DVR and then a TiVo since the Fall of 2007 and with each the HDMI Surround sound performed flawlessly.

While my Yamaha supports a digital connection, it will not support HDMI video and a digital connection concurrently, as HDMI audio has a higher priority. And no, I am not changing my video connection too.

Beside, why should I rewire my entertainment system when the problem is circumvented by using the Stereo mode of the ATT DVR (which is unacceptable) and is resolved by rebooting the ATT DVR.

I have seen several other users with the same intermittent garbled/crackled sound when in Surround Sound mode but probably not in sufficient numbers to get a resolution from ATT. Could it be a defective ATT DVR maybe but I have not seen any symptom/fix information for that.

The reason why I purchased a TiVo when I was on Time Warner Cable was due to the unreliablility of the TWC DVR. The TiVo was a great solution except for the required Channel Adapter. Eventually the TWC service became really flakey so I moved to ATT U-Verse.

As I said earlier, I will try to get more failure senerios this weekend.

[ApexRon]

Okay, research is done for the garbled/crackled Surround Sound audio issue. I even have a recording to share, just send me an email address.

In Surround Sound mode, audio drops are extremely infrequent and typically almost unnoticeable but still there. And most importantly, the audio drops are not concurrent with my garbled/crackled issue.

Garbled/crackled issue observations:

• Can be a gradual change from normal sound or all at once
• At times merely changing to Stereo will resolve but at times a restart of the Cisco IPN4320 is required
• Can occur either with live or recorded programming
• Watching 1017, local NBC in HD, creates a challenge for any entertainment system as there many switches between 1080i, 720, and probably 480 with corresponding changes from Surround Sound to Stereo and back again. All this is because of switching between national feeds, local feeds, and commercials during the Today Show. However, all this does not cause the garbled/crackled issue to occur.

If ATT U-Verse is monitoring this, I am willing to work with anyone to further identify root cause even though I am satisfied that it is something in the Cisco IPN4320. I would even be willing to beta test a potential fix or an on-site visit. Whatever it takes!

[ApexRon]

Okay, I have replaced HDMI cables to my Yamaha YSP-4000. Still intermittent garbled sound. I switch inputs between BlueRay and Cisco, same symptom (what are the odds of two inputs having the same intermittent garbled sound?). I have found that there are three ways to get rid of the garble; 1) reset the ATT Cisco box, 2) power cycle the Yamaha box, and 3) change ATT Cisco box to Stereo rather than Surround Sound.

My opinion is that something the ATT Cisco box is doing with the HDMI interface (clocking issue??) is the root cause. And any kind of HDMI reset will clear the garbled sound.

My next step is to line up ATT to come out and replace the Cisco box but that may take a couple of weeks due to my availability.

[PanellaM]

I too, went thru the same pains as you have with my audio issues and the DVR box. I did have my Cisco box replaced and the problem persisted. Seems U-verse has a "known" issue with the Cisco box and using the HDMI connections. The only thing that resolved my problem and was suggested by the technician that came to my home was to use the Component connections between the DVR box and my HDTV. I'm very frustrated that not only does U-verse NOT support 1080P and 120hz for my new t.v, but now I have to "dumb-down" the connections to match their equipment, instead of them upgrading equipement that works with the HDTV's.

[ApexRon]

I was asked by ATT to try using something other than HDMI, I refused. ATT and Cisco need to fix, period.

I am trying out methods to recover from the garbled sound. I believe a simple reset to HDMI interface could do it but how to accomplish that without power cycling the Cisco box or my audio equipment.

Having moved from a Time Warner Cisco box to TiVo, I can tell you that the ATT Cisco box is the best of the worst.

[ApexRon]

Talk about timing, the garbled audio just happened and here is how I resolved it for now:

1. Paused the TV program
2. Removed and then re-plugged the HDMI cable at the back of the ATT Cisco box
3. Started TV progam

I was right, a simple HDMI reset resolves.

[SomeJoe7777 ACE - Geek]

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ApexRon wrote:

I was asked by ATT to try using something other than HDMI, I refused. ATT and Cisco need to fix, period.

---

I understand the frustration and yes, the root of the problem is a poor HDMI implementation on the U-Verse STBs.  But why live with the problem when there are viable work-arounds?  In the end, you want trouble-free TV viewing, correct?

Why not either:

1) HDMI directly to TV for video and optical to Yamaha for audio?  If you have a programmable remote like the Logitech Harmony series, the U-Verse Activity can be programmed to change all input settings for you.

2) Component video (Y-Pb-Pr) and optical audio to Yamaha, which will be converted to HDMI and sent to the TV?  (Assuming your Yamaha can do this -- some receivers can't, and only function as an HDMI router).

Both of these should give you trouble-free viewing without worrying about HDMI resets.

[ApexRon]

The audio drop outs are not a big deal and the garbled sound usually occurs once during our evening viewing and infrequently two or three times.

The audio amp (Yamaha YSP-4000) is the hub of our entertainment center. From it I choose the source (FM radio, MP3, turntable, BlueRay DVD, or ATT U-Verse). Both the BlueRay DVD and ATT U-Verse are using HDMI and the Yamaha is smart enough to automatically power up and switch to either when they are powered up.

The ATT U-Verse remote does not recognize my Yamaha. I control volume via the TV which knows to control the Yamaha because of the HDMI interface. I had a Logitech Harmony years ago and it is currently in a landfill.

While the Yamaha can output to HDMI from non-HDMI inputs, this would mean a big bulky RGB cable. And unfortunately because the Yamaha is smart, I would have to run a fiber cable for audio from ATT U-Verse due to the fact the Yamaha knows when an active HDMI cable is plugged in and automatically ignores other inputs.

Not all circumventions are necessarily worth it. Consider the Pinto. To minimize the gas tank from exploding upon rear impact all the user had to do was keep a maximum of a gallon of gas in the tank at a time.

Thank you for your suggestion.

[oufanindallas]

This was posted  in the other thread regarding audio drops.  Seems AT&T is not the only one to experience it.  Direct TV is having the issue also Direct TV audio drops  I did a search and came up with many more.  And here everyone claims that DTV is so perfect.

[ScottMac]

To which level is your HDMI cable certified? Is it 1.3, 1.3a, 1.4a ?

[SomeJoe7777 ACE - Geek]

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ScottMac wrote:

To which level is your HDMI cable certified? Is it 1.3, 1.3a, 1.4a ?

---

HDMI cables don't have an HDMI version certification.  The 1.x version number is the protocol version which runs over the cable and is specific to the devices, not the cable.

Cables are rated based on a category.  Category 1 HDMI cables are rated to 75 MHz and can carry 720p/60, 1080i/30, or 1080p/24 at 8-bit color depth (these are also called "standard" HDMI cables).  Category 2 HDMI cables are rated to 350 MHz and can carry higher resolutions, frame rates, and color depths (these are also called "high-speed" HDMI cables).

See Blue Jeans Cable for additional explanation.

[ScottMac]

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SomeJoe7777 wrote:

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ScottMac wrote:

To which level is your HDMI cable certified? Is it 1.3, 1.3a, 1.4a ?

---

HDMI cables don't have an HDMI version certification.  The 1.x version number is the protocol version which runs over the cable and is specific to the devices, not the cable.

Cables are rated based on a category.  Category 1 HDMI cables are rated to 75 MHz and can carry 720p/60, 1080i/30, or 1080p/24 at 8-bit color depth (these are also called "standard" HDMI cables).  Category 2 HDMI cables are rated to 350 MHz and can carry higher resolutions, frame rates, and color depths (these are also called "high-speed" HDMI cables).

See Blue Jeans Cable for additional explanation.

---

Yes, understood. But the packaging usually has some verbiage indicating the highest level the physical hardware will support. Whee I was going was that many of the uber-cheap cable available over the Internet are not rated / certified for 1.3a (some/many are 1.2 or unrated crap).

[SomeJoe7777 ACE - Geek]

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ScottMac wrote:

Yes, understood. But the packaging usually has some verbiage indicating the highest level the physical hardware will support. Whee I was going was that many of the uber-cheap cable available over the Internet are not rated / certified for 1.3a (some/many are 1.2 or unrated crap).

---

Many packages do indeed say a 1.x rating, but that is meaningless.

Any standard category 1 HDMI cable fully supports any protocol standard up to and including HDMI 1.4.  The resolutions, frame rates, and color depths may be limited to standard broadcast signals, however.

And yes, many HDMI cables aren't certified at all for any category of operation.  This includes the famous Monster cables, which don't have a certification for anything.

[ApexRon]

ScottMac,

My newly purchased cables are:

• Mediabridge Ultra Series - High Speed HDMI Cable With Ethernet - Category 2 Certified - Supports 3D & Audio Return Channel - (10 Feet)

• Supports 3D Technology, 4K, Ethernet Channel, Audio Return Channel, 1440p and 1080p FullHD Resolution

• Category 2 Certified - High-Speed 10.2 gbps / 340 MHz (Supports Increased Refresh Rates and 48-Bit Deep Color)

• Fully Shielded Heavy Duty 28 Gauge Premium Grade Cable with Soft PVC Jacket

[farmerjohn]

I'd agree with the debatable pedigree of some cable construction. However, in my communications hardware experience cables used indoors will probably be bad all or most of the time or good all the time unless they have an environmental condition that changes through the day. I also have a 15 meter "no name internet" HDMI cable that has never exhibited any problems as well as a 6 footer ($2.50). That is with my Vizio TV. Our other TV (720P Olevia) and primary box regularly have the garbled audio. Like you stated, it doesn't matter when, what, or how you are watching, the garbling occurs on its own schedule. We've recorded a string of garbling and then the playback is clear and vice versa.

Sounds like software/hardware implementation to me but is it the boobtube or the ATT box or a combo?  :-(

[ApexRon]

FarmerJohn,

The garble audio is 100% the ATT box.

Long story short... the ATT box has a buffering/sync problem in passing data from the network to the HDMI interface. Not sure why it only seems to affect audio. Anyhow, this is why the garble problem can be circumvented by not using the HDMI for audio.

Realize the ATT box is a Cisco product that ATT remarks. And the ATT box is running Windows CE (down level) with special code to support this solution. Now the question becomes; is it the hardware or the software? Also realize that the garble may be an indirect result of ATT network issues. This is the old situation of "if it hurts when you do that, just don't do that".

What are the options?

1. Fix the ATT network issue. That could be very expensive.
2. Fix or redesign the Cisco hardware to accommodate the ATT network issue. Fairly expensive to accomplish but outrageously expensive to rollout (a dispatch to every U-Verse customer).
3. Fix or redesign the Windows CE or other software. Lowest cost to accomplish and rollout. However, is it probable that this will resolve the issue. Unknown.

So here we sit waiting for something to happen.

[farmerjohn]

If the network is involved how can recorded shows that were received with no garbling play back later with the garble? Of course there could be more than one way to generate the garbled HDMI audio.

It doesn't sound like holding our breath waiting for a fix would be very productive.

[ApexRon]

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farmerjohn wrote:

If the network is involved how can recorded shows that were received with no garbling play back later with the garble? Of course there could be more than one way to generate the garbled HDMI audio.

It doesn't sound like holding our breath waiting for a fix would be very productive.

---

FarmerJohn,

I agree that a network issue should not be causing garbled HDMI audio when playing back a previously recorded program. Moreover, if you noticed, when you rewind the recording and playback over the time frame it was garbled, the audio probably would not be garbled again. However, this is what I was told.

Realize that the ATT box is Windows CE and having dealt with Windows' challenges spanning several decades, I can state that a network issue could still be the root cause. However,I suspect that even if you disconnected the ATT box from the network, the garbled audio may occur, though less frequently because of the way Windows CE and the ATT box with associated drivers for the windows hardware support work. Windows CE is interrupt and priority driven, thus if something more important than streaming data to the HDMI interface happens, that streaming could skip a beat. Skipping a beat should not be an issue if sufficient buffering existed. It is my understanding that part of the ATT box fix is to increase the size of buffers.

This is speculation on my part but this may be how it all works; a block of data (from hard drive or network) is queued up to go out the HDMI interface. The queue has a physical size and probably is a software queue that is made up of memory. Getting the block of data on and off a queue is accomplished by buffering the data. Buffers again are probably software buffers made up of memory. Both buffer and queue sizes can probably be adjusted, but the kicker is that the higher layers (application) must know that larger buffer and queue sizes are available and be programmed to take advantage of it.

As you can imagine, this has got to be a nightmare for ATT in coordinating effort (re-design and testing) with vendors.

I highly suspect that by the time a fix comes out, a new generation of ATT boxes will be available to the consumer for a fee. That is what most electronic manufactures do.

[cwall64]

Everybody seems to be talking about garbled or cut-out audio - I have no audio when I turn on the STB and the Plasma, until I either change inputs (i.e. - switch from HDMI1 to HDMI2 then back) or in the actual HDMI1 settings for audio switch from "Digital" to another setting then back?!?!  My audio output on the ATT box is set to 5.1.  The TV is a Panasonic TCP50S2, and I was concerned as to whether it was a faulty TV or the STB?  I contacted ATT and they said to switch to component cables and that it was a known issue...  Wow, great service - they are starting to look a lot more like comcast!!!  The U-Verse box is the Motorola VIP1200.

[aviewer ACE - Wizard]

I believe your TV is not capable of decoding the 5.1 and defaults to mute. Not sure how you get it to have audio.

I think the only reason to set the STB to 5.1 would be if you have a home theater box & speakers.

I think I did see that 5.1 does not work on HDMI & you need an optical connection to make it sort of work.

My panasonic is mute when the stb is set to 5.1. I will have to see if it comes on when I change inputs.

Also, I notice my Panasonic allows for a separate analog sound input when connected HDMI. Does yours? 

Why not change the STB output to stereo.

[cwall64]

Well, it has to be set to 5.1 to pass through to amp in 5.1, otherwise the amp displays 70mm (not DD)...  The TV is capable of passing all the different signals back to the AMP in the TOSlink cable and it works fine after changing from HDMI1 to 2 and back.

[aviewer ACE - Wizard]

Your problem is not sound from the TV. It is sound from the receiver as passed through the TV. Is that correct?

Not sure about how your TV works, but I will throw out some things to try -

1) My TV has settings for the HDMI Audio - Digital/analog/auto - default is auto - If yours is set to auto it may not be working at first. Changing inputs causes it to select the option that works. Maybe you have another setting that needs to be adjusted.

2) Try a different HDMI input

3) Are you indicating that you cannot connect the STB directly to the receiver? Can you do it just as a test?

[ApexRon]

I now have a workaround for the crackling sound when I attempt to use Surround Sound, well at least for movies.

I no longer watch movies from ATT. Instead I use my Samsung Blue Ray player to connect to Vudu, Netflix, or Cinemanow and watch a movie through one of those sources, typically Vudu. The movie plays in HD and Dolby Surround Sound perfectly, using the same sound system and cable path that has problems with ATT STB Surround System. Hmmm, do you think it is the ATT STB that has the issue?

So the bottom line, movies are no longer an issue with crackling Surround Sound because I don't use ATT for movies. And as an additional bonus, my movies cost a $1 less than the same movie on ATT.

In conclusion, ATT has lost my movie business because they cannot resolve their issue with Surround Sound.