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Help Me Understand The HDMI 5.1 DD Issue


Help Me Understand The HDMI 5.1 DD Issue

I have a Cisco IPN-4320 DVR connected to my tv with HDMI.  I have optical from the DVR to an Onkyo surround sound receiver.  Normally, I watch tv with the surround sound system turned off.  I get sound from the DVR to tv via HDMI.  When I want surround sound, I turn on the Onkyo receiver and get sound from the DVR to Onkyo via optical.  If I leave the Cisco DVR set on stereo, I get simulated surround sound, or I can change the DVR to surround sound and get 5.1.  I would prefer to just leave the DVR set on surround sound, but if the Onkyo is turned off, I don't get any sound from the DVR to the tv via the connected HDMI cable.  Why is that?  This is the exact same setup I used with Charter cable and it worked.  I did a search here and found threads where people are saying U-Verse now transmits 5.1 via HDMI.  Is that not correct or is there something about the way I have my DVR wired that is preventing this?  I'm confused on this issue.  Thanks.

Message 1 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

I think the reason you get no TV sound (when set to surround) is that the DVR is programmed to send appropriate sound signal via HDMI based only on your manual options setting.

It expects you to specify whether or not your TV is capable of decoding surround,

Seems like the HDMI connection should have the TV specifying what sound to send, just like it does the aspect option.

If you connect with component cables your manual option setting applies( like it does on the optical sound output). If you connect with HDMI the HDMI interface specifies the aspect setting - watch the blue light go out.

In the real world if there are two outputs, there need to be two option settings.

In the case of HDMI sound the response to what the TV requires is missing. Therefore, there is no auto switch between HDMI connected devices an optical connected devices.

For the aspect option, it can get in the way trying to use component for one device and HDMI for the other.


Maybe the bottom line is that the manual option should only apply to the analog output (component or optical)  and the HDMI option should be determined by feedback from the receiving device (usually TV).

Message 2 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

Thanks, but can you simplify this to something I can understand?  With the DVR set to surround, does it send a signal to the tv via HDMI or not?

Message 3 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

When set to stereo, the U-Verse boxes output PCM (uncompressed) 2-channel audio on both the optical and HDMI connections.

When set to surround, the U-Verse boxes output Dolby Digital (compressed) 5.1-channel sound on both the HDMI and optical connections.

The cause of your problem is that your TV does not support Dolby Digital audio over HDMI. So when you have the box set to surround, the TV will not get audio.
Message 4 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

Ok, now that's an explaination I can understand.  I'll check my tv manual and see if there is a setting to allow 5.1 over HDMI.  Now, why did it work with the Charter Motorola box?  Does that mean the Charter box could output 5.1 over optical and stereo over HDMI at the same time?

Message 5 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

Actually, that can't be the problem.  I have a blu-ray DVD connected by HDMI to my receiver and HDMI from the receiver to the tv, and I get surround.  So, the tv does accept 5.1 via HDMI.

Message 6 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

OK, I've read enough threads and Google searches that I'm sure this is a U-Verse problem.  My equipment or wiring setup is not the problem.  I guess I could try and have AT&T swap out my Cisco DVR, but I don't think I'm up to that hassle.

Message 7 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

Interesting...my two Cisco set-top boxes don't have this problem.  Just the Cisco DVR.  Maybe I should move the DVR to the bedroom, where I don't have a surround sound system and put a set-top box in the family room, where I have the surround sound system.

Message 8 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

Does anyone have anymore ideas on this?  I have tried the on-line chat support to no avail.  I have tried unplugging the optical to my receiver and R/L audio to my Slingbox to no avail.  I have tried resetting the RG and DVR to no avail.  I tried to enter a work order on the U-Verse website, but it just took me in circles and I was unable.  Is there an internal menu (hidden menu) somewhere on the Cisco IPN4320?   How is the easiest way to request at&t bring me another DVR?

Message 9 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

I think I need to narrow this down and determine if the problem is the Cisco DVR or my Samsung tv.  The fact that I don't have this problem in two other rooms with Cisco STB's makes me think it's the DVR, but those are also newer Samsung tv's.  Later today, I'll bring the small flat screen tv from the kitchen and plug it into the DVR and see if I am able to leave it set on surround.  If so, then it's my tv.  If not, it's the DVR.  If the problem turns out to be the DVR, then I may move it to the bedroom and put a STB in the family room.  That would be easy enough except I have my Slingbox and Roku connected to the DVR.

Message 10 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

OK, I figured it out.  It's this particular Samsung tv and how it handles 5.1 over HDMI.  It is supposed to accept it, but for some reason, it won't accept it from the Cisco DVR.  There must be something about the way U-Verse sends it that the tv can't deal with.  To verify this, I moved our small Samsung flat screen from the kitchen and plugged it into the HDMI cable from the DVR and was able to receive sound via HDMI.  So, I think my choices are to just deal with it or switch from HDMI to component cables.  I might also be able to simply add R/L audio cables from the DVR to my tv for sound and keep HDMI for video.  There is a set of R/L jacks on my tv that are assigned to one of the HDMI jacks for use with DVI.  I think I'll try that first.

Message 11 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

It appears the only work around is component cables.  I did some research on my model Samsung tv and there are issues with HDMI.  Some people have replace circuit boards, etc. to resolve the issue, but it's not worth that for me.  I would switch to component, but I would have to downgrade my Slingbox from component to S-video or move the Slingbox to another tv.  So, for now, I'm stuck with having to manually switch back and forth between stereo and surround.

Message 12 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

You did not report on why the analog Jacks did not work. This is the thing I suggested in the beginning. What is your model TV? I will look at the manual to see if there is a setting. Better yet post the link to the manual.

Why not move the DVR (as you proposed) With phase 2 the DVR needed to be at the most used TV to allow backup of live TV. With phase 3 the DVR should be at the least used TV to open up the extra channel.

If you want to use component, you can connect both slingbox and TV with Y connectors.
Message 13 of 23
Not applicable

Re: Help Me Understand The HDMI 5.1 DD Issue

If it's any consolation, I have 2 Sony flat screens.  One is a 40XBR3 and the other is a 52XBR9.  The 40XBR3 will not get audio thru the TV speakers if set to "surround" but the 52XBR9 will.  The 40 only has 2 built in speakers and the 52 has 4.  Nothing I can do to make the 40XBR3 receive surround though.  I guess it's just to old.

Message 14 of 23

Re: Help Me Understand The HDMI 5.1 DD Issue

I don't know why the analog jacks won't work, but I just get a pop, then nothing. I think the audio follows the video and needs a video source to activate the audio.  My tv is a Samsung LN-S4096D.  There are no options for mixing and matching video and audio sources.  There are lots of threads about defective boards, etc.  Swapping the DVR and STB would not solve the problem.  Also, it's just my wife and I and we rarely use more than 2 HD streams at a time.  I guess I could use Y-connectors if I wanted 10 wires hanging behind my tv in addition to a bunch that are already back there.  Thanks.

Message 15 of 23
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