WebGL memory leak related to audio source

Edit:
It looks like this is a Unity bug. I've tried on the latest 2019 version of Unity and the same thing happens. I also created a brand new project with only one game object in the scene with an audio source attached with "loop" and "play on awake" set. After a few minutes of running, setPosition starts to stack up in ms and the game gradually runs slower.


I'm getting this crazy memory leak related to the audio sources in WebGL version of my game. It starts off fine running at 60 FPS, even more if you uncap it. But over time the FPS gradually lowers to the point where it's unplayable. As soon as I destroy all of the audio sources in the scene the FPS is back to normal though.

My temporary fix is to just remove sound in the WebGL version of my game until I figure out how to add audio sources back in. iOS, Android, Standalone Mac/PC all work perfectly. And this happens in every browser on Mac and PC. I'm using Unity 2018.3.8.

Here's what the call tree looks like in Chrome's developer tools after letting the game run for an hour.



Here's what my audio source setup looks like. There are multiple audio sources and they're referenced in CharacterSounds.cs. I expanded one of the audio sources to show what they look like. Most have loop checked and have an audioclip attached. There is also an audio source somewhere else in the scene for the background wind sound. That one has loop and play on awake checked off. I thought the FPS drop may have had something to do with the multiple audio sources and CharacterSounds.cs script, but even when those are removed the one wind audiosource still causes an FPS drop. It just happens a little slower.



And here is what CharacterSounds.cs looks like:

Code (CSharp):

1. using UnityEngine;
2.  
3. public class CharacterSounds : MonoBehaviour {
4.     private Character character;
5.     private TurnController turn;
6.  
7.     [SerializeField] private AudioSource swishSource;
8.     [SerializeField] private AudioSource slideSource;
9.     [SerializeField] private AudioSource windSource;
10.     [SerializeField] private AudioSource railSource;
11.     [SerializeField] private AudioSource impactSource;
12.  
13.     [SerializeField] private AudioClip snowImpact;
14.     [SerializeField] private AudioClip railImpact;
15.     [SerializeField] private AudioClip crashImpact;
16.  
17.     [SerializeField] private float maxSlideVolume = 0.32f;
18.     [SerializeField] private float slideMultiplier = 0.05f;
19.     [SerializeField] private float swishInterpolant = 3f;
20.     [SerializeField] private float swishMultiplier = 10f;
21.     [SerializeField] private float maxWindVolume = 0.05f;
22.     [SerializeField] private float windMultiplier = 0.1f;
23.     [SerializeField] private float maxRailVolume = 0.05f;
24.     [SerializeField] private float railMultiplier = 1f;
25.     [SerializeField] private float impactMultipler = 0.5f;
26.  
27.     private float lastHorizontal;
28.     private float swishVolume;
29.     private float slideVolume;
30.     private float railVolume;
31.     private float windVolume;
32.  
33.     void Awake () {
34.         character = GetComponent<Character> ();
35.         turn = GetComponentInChildren<TurnController> ();
36.  
37.         if (character == null) {
38.             Debug.LogError("No Character script attached");
39.         }
40.         if (turn == null) {
41.             Debug.LogError("Could not get TurnController on Character");
42.         }
43.     }
44.  
45.     void Start () {
46.         slideSource.Play();
47.         slideSource.volume = 0f;
48.  
49.         swishVolume = 1f;
50.         slideVolume = 1f;
51.         swishSource.Play();
52.         swishSource.volume = 0f;
53.  
54.         railSource.Play();
55.         railSource.volume = 0f;
56.     }
57.  
58.     void OnEnable () {
59.         turn.OnLanded += OnLanded;
60.         character.OnEatShit += OnEatShit;
61.         character.OnRestart += OnRestart;
62.     }
63.  
64.     void OnDisable () {
65.         turn.OnLanded -= OnLanded;
66.         character.OnEatShit -= OnEatShit;
67.         character.OnRestart -= OnRestart;
68.     }
69.  
70.     private void OnLanded (LandingInfo landingInfo) {
71.         AudioClip audioClip = null;
72.         if (landingInfo.surface == Ground.Surface.Rail) {
73.             audioClip = railImpact;
74.         } else if (landingInfo.surface == Ground.Surface.Box) {
75.             // TODO should be boxImpact audio clip
76.             audioClip = railImpact;
77.         } else {
78.             audioClip = snowImpact;
79.         }
80.  
81.         impactSource.pitch = Random.Range(0.8f, 1.0f);
82.         impactSource.PlayOneShot(audioClip, landingInfo.impactForce * impactMultipler);
83.     }
84.  
85.     private void OnRestart () {
86.         railSource.Play();
87.     }
88.  
89.     private void OnEatShit () {
90.         impactSource.PlayOneShot(crashImpact, 1f);
91.         railSource.Stop();
92.     }
93.  
94.     void Update () {
95.         if (!turn.currentlyColliding) {
96.             swishSource.volume = 0f;
97.             slideSource.volume = 0f;
98.             railSource.volume = 0f;
99.             return;
100.         }
101.  
102.         float magnitude = Mathf.Abs(turn.rb.velocity.magnitude);
103.         float deltaHorizontal = 0f;
104.  
105.         if (character.horizontal > 0f) {
106.             if (character.horizontal > lastHorizontal)
107.                 deltaHorizontal = character.horizontal - lastHorizontal;
108.         } else {
109.             if (character.horizontal < lastHorizontal)
110.                 deltaHorizontal = character.horizontal - lastHorizontal;
111.         }
112.  
113.         if (character.ground.surface == Ground.Surface.Snow) {
114.             swishVolume = Mathf.Lerp(swishVolume, Mathf.Abs(deltaHorizontal) * swishMultiplier, swishInterpolant * Time.deltaTime);
115.             slideVolume = Mathf.Clamp(magnitude * slideMultiplier, 0f, maxSlideVolume);
116.             windVolume = Mathf.Clamp(magnitude * windMultiplier, 0f, maxWindVolume);
117.  
118.             swishSource.volume = swishVolume;
119.             slideSource.volume = slideVolume;
120.             railSource.volume = 0f;
121.         } else if (character.ground.surface == Ground.Surface.Rail || character.ground.surface == Ground.Surface.Box) {
122.             railVolume = Mathf.Clamp(magnitude * railMultiplier, 0f, maxRailVolume);
123.             railSource.volume = railVolume;
124.         }
125.  
126.         windSource.volume = windVolume;
127.         lastHorizontal = character.horizontal;
128.     }
129. }

 

Hi,
Have you solved this issue ? Or tried any other plugin for AudioSource ?

 

Jumping in to hopefully get some insight on this too. I'm seeing this exact same thing across all browsers in my WebGL builds, it seems like Edge handles it the worse (tested in latest 2018 version up most recent 2019 version all with same results).

Currently I have a test scene setup with only a main camera, directional light, and 7 cubes - each with an audio source that loops and plays on awake (all with the same clip plugged in), there are no scripts at all. Within about 10 minutes of profiling my WebGL build you can see performance start to drop as the AudioSource.Update process time steadily increases. I have seemingly tried every type of audio file type, import setting, audio play/pause/stop (play, playoneshot, playclipatpoint, etc), instantiate/destroy AudioSource, combination to see what may be increasing the process time of the AudioSource calls, but nothing helps.

I'm honestly surprised this is not a bigger issue as it's a show stopper for any type of development in WebGL that uses the integrated AudioSource.

 

Nope, I still haven't solved this. I'm glad I'm not the only one having issues. Let's hope WebGL audio gets fixed soon.

 

It might be browser bug in the setPosition method
https://developer.mozilla.org/en-US/docs/Web/API/PannerNode/setPosition
but maybe one solution would be to check if the position changed before setting it again.

You can try to add "soundsetpos.jslib" to Plugins/WebGL folder

Code (JavaScript):

1. var LibrarySoundSetPos = {
2.   JS_Sound_SetPosition: function (channelInstance, x, y, z) {
3.     if (WEBAudio.audioWebEnabled == 0 || (
4.         WEBAudio.audioInstances[channelInstance].panner.positionX == x &&
5.         WEBAudio.audioInstances[channelInstance].panner.positionY == y &&
6.         WEBAudio.audioInstances[channelInstance].panner.positionZ == z)) {
7.       return;
8.     }
9.     WEBAudio.audioInstances[channelInstance].panner.setPosition(x, y, z);
10.   }
11. };
12. mergeInto(LibraryManager.library, LibrarySoundSetPos);

 

Ok it didn't help, the position is set according to the pose related to the audio listener, and not related to the world.
So it did updated the function, but setPosition still get calls in most of the frames.

Did it happened to you only in Chrome, or also in Firefox?

 

hello

this is the response we got from a support ticket:

followed by:

lastly, we did not have the issue with Firefox, and are currently using a work-around with an audio-based jslib injection.

 

I'm having the same issue with 2019.3.12f1. The WebGL version of our game just grinds to halt over time, as the audio clips start playing slower and more distorted over time. Disabling all audio the WebGL version runs fine.

If it's playing the clips slower then it could be a 3d positioning thing possibly. If it's trying to alter the pitch not sure whats going on with this bug.

PSD

 

We upgraded Unity to 2019.4.19f1 and still got this same problem.

 

This was fixed in 2021.1.X:

https://issuetracker.unity3d.com/is...hen-playing-audiosources-on-chromium-browsers

 

Nope, still happens in 2020.3.23f1. I re-enabled sounds in the WebGL version of my game as a test and took this screenshot after letting it run for 30 minutes. My game becomes completely unplayable getting only 1 or 2 FPS. I don't even use SetPosition anywhere in my game.

Edit: Oops, I misread the Unity version. I will check out 2021.1