Surround sound issue (ATSC3)

Dialog is playing ONLY out of the left rear channel. When I turn off Surround Sound, dialog ONLY plays out of the left front speaker.

The Sound Test successfully identifies each speaker channel.

I am using an HDHOMERUN ATSC 3.0 quad tuner, with an AppleTV 4K.

I have power-cycled the AppleTV, the network tuner as well as the antenna’s amplifier and the issue is still ongoing.

The AppleTV accurately plays audio accurately for other media.

To make things more complex, SOME HD stations have this problem, others don't (I wonder if it's because the trouble-free programs are broadcasting in stereo but not 5.1).

Also worth mentioning....when trying to watch the problematic stations on a web browser on a laptop, no audio plays at all....but audio plays when I'm watching stations that arent' having this problem (again.....perhaps because they aren't doing 5.1 sound?)

Somebody please help, this issue recently started happening and it is annoying.

Looking further into this, I browsed to the HDHOMERUN ATSC 3.0 tuner's page and saw that the channels in which I am having audio problems have HEVC and HD flags next to them. The ones without audio problems only show an HD flag. What exactly does this mean? The common denominator seems to be the HEVC flag....

It means the video stream for that channel is being broadcast in H.265/HEVC format. If there is nothing there (other than "HD"), then it is H.262/MPEG-2 video; if it says "AVC", then the video is encoded as H.264/AVC (what some commonly call "MP4").

If the video is broadcast as HEVC, then it is likely the audio is AC-4. The SD forums are filled with users complaining about the audio from ATSC3 broadcasts.

Have you tested the problem channel in SD's HDHomeRun software? What about in VLC? Is the problem the same in other programs?

I just tested this with SD's own audio coming from the channels with the HEVC flag at all (but on ChannelsDVR on my AppleTV, I get dialog playing out the wrong speaker)

So I found something out....

These stations that I am having trouble with are actually ATSC 3.0 stations.

Tampa just turned up ATSC 3.0 two days ago!

So I emailed Silicon Dust to report the audio issue and was given an immediate reply...

“Those are ATSC 3.0 stations, and we are still working out some of the kinks in getting those stations to work in the HDHomeRun app. We have another update coming out soon for the Apple TV 4K that should fix the audio.

  • Silicondust Support”

So SD is working out this issue for their app.

So can the developers of ChannelsDVR possibly provide a fix for their app? These are ATSC 3.0 stations that I am currently having the problem with

It could be your local broadcast is not using the correct format yet as the broadcasts are brand new.

If you email support a sample from the tuner it will help us look into things further.

This may sound stupid, but what is support’s email, and how do I acquire a sample for them to analyze?

[email protected]

As far as getting a sample, see this article:

Scroll down to "How do I capture a video sample to troubleshoot player issues?"

You can click any header in the docs to get a direct link:

Thank you. I have emailed support the capture.

I did send in the capture you have requested to Support.....has anybody looked into this yet?

We got it but have not looked yet. Chances are this will be fixed in the next HDHR firmware release

Just a heads up, I tried using my antenna with the HDHOMERUN app, instead of ChannelsDVR on my AppleTV 4K, on an ATSC 3.0 channel.

Audio plays perfectly!

So what can I provide to help support find the fix for this???

Video still skips here and there

issue still persists, even after yesterday's Channels update. I went into the AppleTV Settings, then Video and Audio > Audio Format > enabled "Change Format" and kept it on Dolby Digital 5.1 as the optimal format.

Now, the dialog comes out of the FRONT left speaker as opposed to the REAR left speaker. I'll take that over the rear left speaker anyday, but even after the app update this is still an ongoing issue for me. Please help. I never had any issues with this until ATSC 3.0 :frowning:

You can try the latest TestFlight beta. It may help, or it may make things worse.

Don't expect a quick fix here. This is experimental technology and you're an early adopter. If you want a stable DVR and live TV experience, you will either need to switch to ATSC 1.0 tuners or wait for firmware updates from SiliconDust which allow you to disable problematic ATSC 3.0 channels.

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Understood. If SD does not enable the option of dropping the 3.0 channels, I may have re-deploy the old HDHR tuner.

Thanks guys!

Ordered a replacement HDHR Connect as I gave my last one away, thinking this awesome new ATSC 3.0 one would be the bees knees when it got deployed in my area. I'll be deploying them both now. I'll have the standard HDHR box as the higher priority tuner. Looking forward to SD getting this fixed.

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Many sound issues were resolved when using the latest hdhomerun firmware along with the latest Channels betas.