Strange issue: Lost voice tracks in center channel (1 Viewer)

[sirkev]

I'm experiencing a an issue with my audio through my home theater.
My setup: NAD T758v2 receiver, M&K K7's for fronts, K5's for the rear, and M&K 12in subwoofer (5.1 setup, I have a small area). TV is an LG OLED55B7P. The problem has occurred across the Directv box, my LG 4K Blu-Ray, and OTA channels.

I can be watching a program on Directv and change the channel and then suddenly the voice audio tracks drop out. For example, I turned over to the Purdue v Wisconsin basketball game last night. Instead of hearing the normal play by play commentary, it sounded like I was at the game. Sounds were coming out of each of the front channel speakers, but it was just the surround/background audio and other arena sounds. It was interesting, because like I said, it was as if you were in the stands at the game. I could hear the PA announcer and everything, but nothing in terms of commentary.
I turned it back on this morning and at first it was fine, but after changing channels a few times, it dropped out again. I went to test it with my 4k Blu-Ray player and put in my John Wick disc, went to the scene where John checks into the hotel. Could hear other sounds, the soundtrack music, but no voice audio. When I went into the disc settings and chose 2.1 instead of the default Dolby Digital Atmos default, then I could hear voice tracks as it was stereo coming out of the left and right front.
I'm starting to think its something terminal, that as it heats up something is shorting out but wanted to find out if anyone else has experienced a similar issue with a NAD receiver or another brand.

Thanks!
Kevin

 

[JohnRice]

Are your sources connected directly to the receiver, or routed through the TV?

 

[John Dirk]

Welcome! This particular NAD product line is somewhat notorious in this regard. I would re-run auto calibration immediately after powering on the system. When the problem surfaces, repeat this procedure and note any differences. If test tone levels mirror the main issue then you probably need to consider replacing the receiver.

 

[sirkev]

Are your sources connected directly to the receiver, or routed through the TV?

Routed through the TV because they are 4k sources (except for the Directv box) and my T758 only has 1080p. I've had the 758 for at least 5 years. It's been great up to now.

 

[sirkev]

Welcome! This particular NAD product line is somewhat notorious in this regard. I would re-run auto calibration immediately after powering on the system. When the problem surfaces, repeat this procedure and note any differences. If test tone levels mirror the main issue then you probably need to consider replacing the receiver.

Thanks, I'll try that tonight. I am bracing for the fact that I will have to replace it. Thinking of getting another T758 now that the v3 has 4k inputs and other upgrades. But I'm open if there is a better sub $2k receiver out there. My viewing area is small so I'd rather have a great sounding 5 or 7 channel with good DACs versus some 9 or 11 channel behemoth that I won't be able to utilize to its fullest.

 

[JohnRice]

I asked because this can be a problem with the receiver properly locking onto the signal, for lack of a better description and can be made worse by using eARC. It can also be exacerbated by a flawed processor or hdmi board. I had a surround processor which had various problems like this which I eventually replaced once I just got sick of it.

 

[sirkev]

Thanks for the suggestions. I re-ran the Audssey calibration. So far things are back to normal, but I haven't run the system for longer than an hour.
I just realized that I have the audio going from the tv to the receiver via a Toslink cable. Could that be causing the issue? It is an older Monster braided optical cable so it might be time to change that out.

 

[Lord Dalek]

Thanks for the suggestions. I re-ran the Audssey calibration. So far things are back to normal, but I haven't run the system for longer than an hour.
I just realized that I have the audio going from the tv to the receiver via a Toslink cable. Could that be causing the issue? It is an older Monster braided optical cable so it might be time to change that out.

Your T758 has an ARC in. No need to use optical with it.

 

[sirkev]

Your T758 has an ARC in. No need to use optical with it.

In my case, my T758 is a v2 without 4k HDMI. So my Directv, Blu-Ray and X-Box X are all plugged into the TV, so the optical is needed to output the sound from the tv to the receiver. I have the receiver tv output HDMI connected to HDMI 4 on the tv so I can see the OSD menus and the non-4k sources (Roku, Switch).

 

[JohnRice]

If you can swing a new receiver, that’s your best solution. Then you can run all the sources through it, as intended.

 

[Lord Dalek]

In my case, my T758 is a v2 without 4k HDMI. So my Directv, Blu-Ray and X-Box X are all plugged into the TV, so the optical is needed to output the sound from the tv to the receiver. I have the receiver tv output HDMI connected to HDMI 4 on the tv so I can see the OSD menus and the non-4k sources (Roku, Switch).

HDCP 2.2 has nothing to do with ARC. You can still have your external devices plugged into inputs 1, 3, and 4 on that TV and still get surround sound as long as the receiver is plugged into Input 2. This was basically the work around back when UHD showed up in 2014. Also DirecTV DOES NOT SUPPORT 5.1 over optical connections so this is really your only option with what you have.

...that being said, get a new receiver. HDCP 2.2 made all the old mid-2010s age like dog years.

 

[sirkev]

Thought I'd give an update since I hate when people don't mention if the issue I got solved or not. So far so good!
Working with NAD support, I was able to update the firmware and I replaced the old optical cable. A few days in including some 4+ hour sessions and no audio dropouts!
One thing to note: When I did the firmware update, possibly because I hadn't done one on the receiver before now, it unpaired the remote. I had to go into the receiver settings, choose Channel 0 and then do a factory reset of the remote. But it all works again.

So at least now I can plan for a future upgrade instead of it being thrust upon me.