Godot: HTML5 Audio Slow / Stuttering on iOS

[davidCentervention]

Godot version: 3.2 (also seeing the same issue with Godot 3.1, and 3.1.1)

OS/device including version: iPad 5th generation running iOS 13.3.1

Issue description: I'm seeing audio playing REALLY slow and stuttering (sounding robotic) on iPad HTML5 builds using .wav and ogg files.

Steps to reproduce: Create a blank project,, add an AudioStreamPlayer and load a .ogg or .wav file in the AudioStreamPlayer and set it to play that audio file on a loop. Export to HTML5 and play on an ipad and the audio will play very glitchy, it will sound slow and robotic.

Minimal reproduction project: https://drive.google.com/file/d/14XzsamzGlBn_vx2y2OXpdhtkwTxjWEco/view?usp=sharing

[Calinou]

@davidCentervention Please upload a minimal reproduction project to make this easier to troubleshoot.

[davidCentervention]

Minimal reproduction project: https://drive.google.com/file/d/14XzsamzGlBn_vx2y2OXpdhtkwTxjWEco/view?usp=sharing

[ChronoDK]

I have this problem as well, but on an iPhone 11 with iOS 13.3.1.
Happens with all sounds, looped or not.

[Julian-Vos]

Same problem here, on an iPad Air 2 with iOS 12.4, Godot 3.1.2.

I spent a few hours trying to work around it, but to no avail. It seemed suspicious that the default sampleRate of the audioContext was 48000 on my laptop and Android phone, which play my HTML5 sounds just fine, yet 44100 on the iPad. However, all my sounds are actually mixed with a sample rate of 44100, and my laptop still plays them right when setting the audioContext's sampleRate to 44100. I cannot set the audioContext's sample rate on the iPad, but resampling the sounds to 48000 didn't change anything. Also, the sounds are played back about twice as slow, instead of the 48000 / 44100 = 1.09x you would expect. Doubling their pitch_scale in Godot made the durations approximately right, but they still sounded robotic.

However, the iPad could play the same sounds just fine when using the Web Audio API directly. Hence I assume the problem can be solved in either Godot or WebAssembly/Emscripten, unless it's a performance/thread problem.

[caizu]

Same here. For me it looks like a buffering as the sounds distort in the beginning / after loading very much but suddenly it might clear up if you play the game further. Another interesting thing is that sounds get better if you minimize the browser. And the sounds continue playing if you close the browser.

Godot version 3.2 Custom (with asm.js support)
iPad mini 2, iOS 12.4 (as well as all other iPads and iPhones we have tried)

[Tinkersedge]

Having the same exact issues. So weird that when you minimize the browser, it plays the sound clear for a couple of seconds. Must be a loading issue of some sort.

Godot version 3.2 - GLES2 build
iphone 11, iOS13,

[Tinkersedge]

Has anyone found a way to make this work yet? A work around?

[Calinou]

@Tinkersedge Not that I know of. See also #26554.

[davidCentervention]

@Tinkersedge For me the work-around was to handle audio entirely outside of Godot for HTML5 for the time being. I call Javascript from Godot to load mp3s from the web into an audio tag on my HTML page and play audio from there, completely bypassing the audio engine in Godot to use the audio played by the browser.

My assumption is the issue in Godot is likely due to the auto-play audio changes that went in most browsers in the last few years that require audio to be initiated by an interaction (click) by the end user: https://webkit.org/blog/7734/auto-play-policy-changes-for-macos/

[Tinkersedge]

@davidCentervention any chance you could share a super simple version of how you did that? Is that method able to handle background audio as well as sound effects? Thank you so much for telling me about the work around. Hopefully I can still make this game happen on tablets.

[ChronoDK]

I tried a lot of things, for instance different sample rates and creating a new audio context. Nothing worked for me. I guess the work-around by @davidCentervention is the only way for now.

[caizu]

@Tinkersedge @davidCentervention @ChronoDK We finally actually managed to solve this: my colleague modified JS audio driver source code and recompiled the Engine's export template. I'll ask him to drop the solution here as well.

[ChronoDK]

@caizu Amazing, I hope the fix can be added to a release soon then.

[caizu]

@ChronoDK I hope it too and I asked my colleague to do that.

[teknobilly]

I'm experiencing this problem with IPads and IPhones in a simple html5 game made with Godot Engine 3.2

my colleague modified JS audio driver source code and recompiled the Engine's export template

I was hoping issue #38215 for v4 might help this case. I managed to hack the AudioServer::Init function and compiled the WebAssembly file with version 3.2.2 source. But am still experiencing the issue.
This is my first foray into debugging source code and I am feeling really happy having achieved this much. But I am still having this issue with Audio on IOS devices new and old, ipad and iphone, with updated IOS.

[thomazette]

Hello people, the great problem is the buffer_size!
Godot audio driver use createScriptProcessor with the first value zero!

So the device, set by default the buffer_size! I dont know why IOS system is so shit, to set 256 on the buffer_size!

I put this trative, when the buffer_size is lower 2048 they set 2048.

Below is the template export with that trative, just extract into folder AppDataRoamingGodottemplates3.2.1.stable

3.2.1.stable.zip

I hope helped sameone!!

[dpensky]

Hello people, the great problem is the buffer_size!
Godot audio driver use createScriptProcessor with the first value zero!

So the device, set by default the buffer_size! I dont know why IOS system is so shit, to set 256 on the buffer_size!

I put this trative, when the buffer_size is lower 2048 they set 2048.

Below is the template export with that trative, just extract into folder AppDataRoamingGodottemplates3.2.1.stable

3.2.1.stable.zip

I hope helped sameone!!

This fixed my issue. Thanks.
I hope they put this on the officials templates

[Calinou]

I hope they put this on the officials templates

Feel free to open a pull request for this :slightly_smiling_face:

[Tinkersedge]

Hello people, the great problem is the buffer_size!
Godot audio driver use createScriptProcessor with the first value zero!

So the device, set by default the buffer_size! I dont know why IOS system is so shit, to set 256 on the buffer_size!

I put this trative, when the buffer_size is lower 2048 they set 2048.

Below is the template export with that trative, just extract into folder AppDataRoamingGodottemplates3.2.1.stable

3.2.1.stable.zip

I hope helped sameone!!

For me, it fixed the ipad issue, but my iphone is back to not loading like it was before the last update. I will try again in case I did something wrong.

[thomazette]

Hello people, the great problem is the buffer_size!
Godot audio driver use createScriptProcessor with the first value zero!
So the device, set by default the buffer_size! I dont know why IOS system is so shit, to set 256 on the buffer_size!

I put this trative, when the buffer_size is lower 2048 they set 2048.
Below is the template export with that trative, just extract into folder AppDataRoamingGodottemplates3.2.1.stable
3.2.1.stable.zip
I hope helped sameone!!

For me, it fixed the ipad issue, but my iphone is back to not loading like it was before the last update. I will try again in case I did something wrong.

Maybe is the buffer lower, the Godot Team put 4096, i set 2048! If dont work to you, i upload with that value to 4096!

[Arbint]

I have tried the template with no luck, so I pushed my butt to learn Java and html 5, and found a solution to play my video through Java:

So basically you use the JavaScript.eval to evaluate your java script to directly add a video player html 5 element to the body of your webpage. That Java identifier is a preload script.

[ChronoDK]

I have found audio to be working just fine on iOS with the latest beta and release candidates, so that javascript workaround should not be needed anymore.

[IvanF]

The issue was connected with size of buffering in platform/javascript/audio_driver_javascript.cpp
there was the part of code:

buffer_length = EM_ASM_INT({
                var CHANNEL_COUNT = $0;
                var channelCount = _audioDriver_audioContext.destination.channelCount;
                try {
                        // Try letting the browser recommend a buffer length.
                        _audioDriver_scriptNode = _audioDriver_audioContext.createScriptProcessor(0, 2, 1);
                } catch (e) {
                        // ...otherwise, default to 4096.
                        _audioDriver_scriptNode = _audioDriver_audioContext.createScriptProcessor(4096, 2, 1);
                }
                _audioDriver_scriptNode.connect(_audioDriver_audioContext.destination);

                return _audioDriver_scriptNode.bufferSize;
        }, channel_count);

and in next string by "// Try letting the browser recommend a buffer length." need to be replaced zero to i.g. 16384. That's it. Safari can not determine the size and it falls to 0 causing crackles.

[akien-mga]

@IvanF Indeed, that was fixed in https://github.com/godotengine/godot/pull/38816/commits/245c179bd31d65c6b31d156c4f6b08647df0e2fe and #39037. The fix is available in Godot 3.2.2.