Channels dropping frames with Nvidia Shield when playing ATSC 3.0 channels

Hi guys, new app user and liking the customization abilities of this app over the old Live Channels app included on the Shield.

One small hiccup though, I get consistent dropped frames, a noticeable stutter on ATSC 3.0 channels. Using HDHomerun. Using the stats feature, I can see the Dropped frames: 0 (decoder) / 129 (output) as an example. And the dropped frames seem to come in bunches, about 15-135 frames every 1-2 minutes. it's a noticeable stutter when it happens too. This is during Live TV playback, I don't have DVR.

And before anyone asks, the signal is strong and clean on my ATSC 3.0 channels. 100% on all three points.
Also, the same channels on the old MPEG2 streams show no dropped frames.

I don't notice seeing this using the Silicondust app.

Other settings. I have the Shield passthrough all audio to my AVR. I have the Channels app set to Surround Sound ON. Video decoder set to Hardware.

Anyone seeing the same thing? What can I do to try and troubleshoot this? I have 4 ATSC 3.0 channels, and all 4 do the same thing.

ATSC 3.0 won't be usable for a year or 3 at least IMO. Audio codec issues and local stations basically in experimentation mode don't make for a very good experience where I live. Can't see how it's going to be much better in other markets.

Meanwhile, stick to ATSC 1.0 stations.

I have a shield tube and also an Apple TV. Had the same issue with atsc 3. The shield is the reason I bought the ATV. Been 100% happy ever since. My shield is still connected but I haven't powered it on in almost a year, I don't miss it at all...

The issue now is ATSC 3.0 is in the alpha stage at the broadcasters. There's no real way the end user can troubleshoot since everything is in disarray with the incoming signals.

The locals in Cincinnati are a mess, but they did move their ATSC 3.0 transmitters to a central tower on a huge hill, so once the technology is stabilized I'll finally be able to receive Cincy stations instead of having to rely on Dayton stations 45 miles away.

It's gonna suck before it gets better in general.

I think everyone here is missing the point of the OP's comment. For OP, the Channels app is dropping frames on ATSC 3.0 channel reception whilst the native HDHomerun app does not. This has absolutely nothing to do with the general state of ATSC 3.0, which admittedly is basically in public alpha testing at this point. OP's comment is specifically about the Channels app.

I can empathize because I often experience a similar issue, except in the opposite. ATSC 3.0 channels on my Nvidia Shields is generally fine (no dropped frames). But live 1080i/1080p ATSC 3.0 channels on my 2021 Apple TV 4K will often experience occasional dropped frames. ATSC 1.0 counterpart channels are fine (different towers so this isn't really relevant), and using the official HDHomeRun app from SD for the same ATSC 3.0 channels does not exhibit the same issue. Similarly, viewing these ATSC 3.0 channels in the Channels app bypassing the DVR is fine as well. Anyway, in my case when using tuning through the DVR Server (which runs on macOS Big Sur), I have found two workarounds:

  1. Go back to the guide and restart the channel – this will sometimes resolve the issue (but not always)
  2. Pause the channel for a few seconds, then resume playback – this fix seems to confirm that this issue is buffer-related in how fast the DVR can transmit the stream to the Apple TV. I have a QNAP 6-disk NAS as my primary DVR storage. The Mac server and NAS are both connected to a 10G switch which then connects to another 10G switch where the Apple TV is then connected, so I doubt this is an internal network bandwidth issue (iPerf3 shows no issues at least)

The issue with dropped frames is fixed in the beta app

2 Likes

Can confirm ATSC 3.0 channels work flawlessly in channels.

The only issue is that my 1080p video I'm getting now is too much for the raspberry pi transcoder to handle. Basically unwatchable in web/or via app with transcoding.

1 Like

Try transcoding to 700kbps. h264 codec is really good. No subtitles though, for some reason option -sn is used with ffmpeg when transcoding.

I've tried that. It doesn't work. Still unwatchable. It will play maybe 10 seconds, then pause. Maybe come back every few seconds, then go out again.

That said, "original" format is pretty compressed. When I'm on LTE on my cell phone, the atsc 3.0 channels can stream from my home to cell phone just fine.