Audio latency when using Android TV clients on some TVs

[safijari]

Describe the bug
So first off I don't know if this is a moonlight bug, but I'm also not sure where else to post this. There is an AV sync problem that appears to be different when using the same client device (I've tried on Chromecast, FireTV, and Nvidia Shield) on various displays. Specifically, the output audio is delayed when playing from the TV. At first I thought this was an issue with a new TV that I had bought but that doesn't seem to be the case. Lemme try to describe what happens as best as I can:

Say I'm using a CCWGTV (4K) and running moonlight on it. If I connect it to my monitor, I notice little to no issues with audio latency. If I connect it to my old TV (some old Samsung LCD TV) I notice a slight audio latency. If I connect it to my LG C1 or Hisense U7H, I notice what sounds like 100ms ish audio latency (i.e the audio is lagging behind the video). On both these TVs, if I connect my Steam Deck instead I see no noticeable latency when using moonlight (which in my mind at least rules out the TV). The latency issue exists in all 3 Android TVs I've tried, with it being slightly less on the Nvidia Shield.

The funny thing is that if I plug in USB headphones directly to the Android TV device, there's no noticeable latency in the audio, so whatever is happening is happening in some HDMI related audio processing. Note that game mode is on on all TVs, and I've tried my best to disable 5.1 audio and any audio processing in all the TVs as well as Android TV devices.

Steps to reproduce
Plug a chromecast or firetv into an LG C1 or Hisense U7H TV and stream your computer to it using moonlight.

Affected games
The issue does not appear to be game specific.

Other Moonlight clients
No, when using moonlight on my Steam Deck and connecting it to the same TVs, there's no audio latency. It appears to be Android TV specific.

Moonlight settings (please complete the following information)
The problem exists with default settings as well.

Device details (please complete the following information)

• Android version: Android 12 or Android 11, depending on device
• Device model: Chromecast 4k, Fire TV 4k max, Nvidia Shield TV Pro (2019)

Server PC details (please complete the following information)

• OS: Windows 10
• GeForce Experience version: unsure, latest at time of filing
• Nvidia GPU driver: latest at time of filing
• Antivirus and firewall software: Windows Defender and Firewall are both on

[allenwp]

I’m not sure this would be helpful, but I made a tool for measuring HDMI audio latency of devices like TVs, soundbars, etc. If you want to rule out audio processing delay that happens with HDMI inputs on your Android TV, you could try measuring its audio latency and compare to other devices that don’t experience this issue.

https://avlatency.com/tools/av-latency-com-toolkit/

[Emmanuel-Tsapekis]

I have precisely the same problem. I have described the issue in this Reddit post
I found that a great way to measure the latency is in the audio settings of the game "Hi-Fi Rush" and this YouTube video
It's definitely the android tv moonlight application. I didn't try on mobile android, but I guess that should be my next try!

EDIT: I just tried on my android phone and would you guess it - no latency! I'm not sure if the android tv app is different from the mobile android app. That could still be to blame if not the OS

[Emmanuel-Tsapekis]

I'm a programmer btw. I haven't worked on Android or even worked open source before, but maybe I should take a look to see if I can't fix it myself. If anyone has advice on where to start looking, that would be great!

[Emmanuel-Tsapekis]

Taking a look, it would seem that it's an android tv OS problem. Maybe it's just my version (android 10) though - I have no way of checking whether it's fixed in android versions 11+

[inox9]

Unfortunately it's still not fixed in Android TV 11 - on xiaomi stick 4k audio is behind video for around 500 ms at least.
Are there any plans on fixing this?

[Hato1]

To add to the list: I also experience this issue (~1 second audio latency) with a Google streamer 4k on a samsung 65" QLED 4K UHD Q75R when using Moonlight.

[awolden]

Same issue
Google tv streamer on Samsung q70 qled. Nothing else on Google tv streamer experiences the delay, only moonlight

[Hato1]

Switching to a Nvidia Shield solved my issue.

[ozkar79]

Does any setting exist in sunshine to fix this audio sync issue? Or can simply changing the delay in some tv setting fix this?

[lightrush]

I don't think Sunshine can fix it. In order to fix it, they'd have to compensate for the delay. The audio and video are produced at the same time on the host and received at the same time on the client. One side, doesn't matter which, would have to delay the video by the amount of audio delay in the TV. But this happens after the audio and video frames have been generated, so as a result, you'd be able to sync the audio and video but both would be delayed by the amount of audio delay. That might make things unplayable depending on the game.

BTW, I tried a USB DAC on my Chrome with Google TV and that eliminated the audio delay via HDMI. NVIDIA Shield has no such delay over HDMI.

[inox9]

Maybe it will help someone.
For now I've kinda solved the issue by using 3.5mm audio jack on my xbox one controller for sound output to my wired headphones while streaming (of course you should check "play sound on PC" in moonlight settings for it to work and mute sound on tv). So, in conclusion - xbox controller is connected directly to pc (not to streaming machine) and acts not only as a controller itself but also as a wireless audio receiver.
I've noticed absolutely no audio delay in this setup.
Of course it will work well only if your pc is not too far away from the place where you are streaming to.

[olibols]

I hit the same Android TV audio-delay class of issue on a Google TV Streamer (Android TV 14): video/input latency was low, but audio was delayed by roughly 0.5s-1s.

I put together a fix here: ClassicOldSong#567

The patch adds a native AAudio callback renderer for Android O+ and falls back to the existing AudioTrack path if AAudio setup fails. It also fixes a preference wiring issue in the Artemis fork where playHostAudio was being passed to the audio renderer instead of enableAudioFx.

Test result: the built APK fixed the Google TV Streamer audio delay first try, with system equalizer/audio effects disabled.