The play() request was interrupted by a call to pause()

[G33kLabs]

Hi,

Sometimes, I've got this error when I load the page :

undefined:1 Uncaught (in promise) DOMException: The play() request was interrupted by a call to pause().

It's happens randomly and when the message is displayed in console : I can't edit dropdown list and text area.

Here is my call code and it happens just after :

        console.log('INJECT BLOCKLY')
        @blockly = Blockly.inject('blocklyDiv', {
            toolbox: @opts.toolbox
            zoom:
                controls: true,
                wheel: false,
                startScale: 0.7,
                maxScale: 3,
                minScale: 0.3,
                scaleSpeed: 1.2
            grid:
                spacing: 25
                length: 3
                colour: '#ddd'
                snap: true
        })

I've tried to delay inject with a setTimeout, but it doesn't change anything.

For information, I use "page.js" for this UI.

Thanks by advance if you've a solution.

[ferrao]

I have the exact same issue, thought it was somehow related to the sounds made by Blocky.

[NeilFraser]

Ah, that makes sense. Try adding a return statement at the top of Blockly.WorkspaceSvg.prototype.preloadAudio_ or comment out the body of that function.

Which browser/OS does this affect? I assume there's no stack track to point back to a line in Blockly that's throwing an error?

[G33kLabs]

Just have tried in private navigation mode, without any plugins and problem is the same.

My chrome version is : Version 50.0.2661.49 beta (64-bit) under OSX 10.11

@NeilFraser > Audio sounds to be the issue : no more problems when commentating internal preloadAudio_

And sounds when dropping elements are stil working.

Blockly.WorkspaceSvg.prototype.preloadAudio_=function(){
    console.log("Sounds : ", JSON.stringify(this.SOUNDS_)); 
    /*
    for(var a in this.SOUNDS_){
        var b=this.SOUNDS_[a];
        b.volume=.01;
        b.play();
        b.pause();
        if(goog.userAgent.IPAD||goog.userAgent.IPHONE)
            break;
    }
    */
};

[NeilFraser]

This is a recent bug in Chromium. Since they appear to be working on it, I don't think we need to think about a workaround at our end. Especially since this is just console spam, with no user impact.
https://bugs.chromium.org/p/chromium/issues/detail?id=593273

[MarkusBordihn]

The linked bug is not really related to this issue.

In the chrome bug the used code is:

    a.pause();
    a.play();

But in this case it's:

    a.play();
    a.pause();

In your case it's expected to get such error message, so this needs to be fixed in the Blockly.WorkspaceSvg.prototype.preloadAudio_ function.

[MarkusBordihn]

Submit a pull request #471 to fix this issue, because is impacting error checking (with catch() { ... }) if you want to make sure that everything is loaded without any errors.

[G33kLabs]

@MarkusBordihn : fix local sources, it seems to solve issues :)

[NeilFraser]

Note that #471 breaks sounds on iOS.

[hugoruscitti]

Is valid to simply disable sound preload ? i make this change to my code and everything seems to be ok:

Blockly.WorkspaceSvg.prototype.preloadAudio_ = function() {};

[NeilFraser]

Disabling preload works, but sounds awful when that first click is offset by up to a second.
I'm still monitoring the open bug on Chrome, https://bugs.chromium.org/p/chromium/issues/detail?id=593273

[hugoruscitti]

thanks!