Why is there a sound delay/reverb sound when adding HD Cable STB?

[Fio]

Here's what I have:

Samsung HLR5067 50" HDTV;
8-year old Sony Dolby digital 5.1 receiver;
Comcast Scientific Atlanta HD STB.

When I got regular TV through Direct TV, I would route the audio through the Sony and get surround sound through the Stereo speakers. The Sony has several sound formats (auto format, normal surround, opera house, stadium, etc) which let me play with the sound.

NOW, I added Comcast HDTV. The service tech routed the component video AND audio (red and white) cables directly to the TV. With this configuration, I can't get TV sound through the stereo speakers.

SO, I found two extra audio out (red and white) plugs in the back of the STB and routed the audio through my Sony receiver, in order to get surround sound when playing TV.

Here's the PROBLEM:

1) There is a noticable delay between the TV speaker and the stereo. It sounds like the stereo speakers are 1000 yards away; they are not in sync.

2) If I disconnect the audio inputs from the TV, OR if I mute the TV sound, the delay goes away. BUT the sound routed through ths SONY, coming through the stereo speakers, has a nasty reverb sound. It sounds as if everything is in a huge gymnasium, and all of the Sony sound formats (auto format, normal surround, opera house, stadium, etc) don' work. It all sounds the same.

3) This problem does not happen with DVDs.

What can I do to eliminate the delay between the TV speaker sound and the stereo sound?

What can I do to enable the Sony receiver to process the sound properly?

Thanks in advance,

- Fio

[mjones73]

First off if you have a dolby digital receiver, try hooking up the audio using an optical cable instead of regular analog stereo audio. Second, it sounds like something is enabled on the input your using for your TV that's modifying the sound, without knowing the model of your receiver, it's hard to offer you advice on what to check on it. If your DVD player is hooked up using analog connections, hook the TV up to it's inputs temporarily and see if the problem still occurs.

[Fio]

First off if you have a dolby digital receiver, try hooking up the audio using an optical cable instead of regular analog stereo audio. Second, it sounds like something is enabled on the input your using for your TV that's modifying the sound, without knowing the model of your receiver, it's hard to offer you advice on what to check on it. If your DVD player is hooked up using analog connections, hook the TV up to it's inputs temporarily and see if the problem still occurs.

The Sony is an STR DE825
I routed the DVD audio out to the Sony using an optical cable. it works fine. I still have 2 or 3 more optical inputs for the Sony (interestingly, the TV/DBS optical audio input on the Sony does not work, so I have to hear DVD audio using the "Tape" optical input on the Sony).

I'll try routing an optical audio cable from the HD STB to an available optical input on Sony.

Should it make any difference whether there are two red and white audio cables going directly from the STB to the TV? These two RCA cables are linked to the component video

Also: should I get rid of the component video cables and instead run a DVI cable from the STB to the TV? I know that DVI gives only video, but from what I hear, DVI is better than component video.

Thanks!

- Fio

[mjones73]

You may see an improvement using DVI, a cable should run you around $20-25 online if you want to try it out.

[57U]

1. See the HDTV FAQ on "DVI/HDMI Information".

2. It's best not to go "through" the TV when listening to audio on the A/V Receiver. You can run the red/white to the TV (when you want to listen to the TV speakers only) and the digital audio to the AVR, but don't go "through" the TV.