W3C home > Mailing lists > Public > public-audio@w3.org > January to March 2015

Re: audioContext doesn't progress on a specific windows 7 machine

From: Raymond Toy <rtoy@google.com>
Date: Wed, 11 Mar 2015 10:20:04 -0700
Message-ID: <CAE3TgXGVxN0fd4gPYhyLCtorBDedSVAJeabMi6GsoGLm3kjRMw@mail.gmail.com>
To: Yehonathan Sharvit <viebel@gmail.com>
Cc: "public-audio@w3.org Group" <public-audio@w3.org>, daniel@audyx.com, Philippe Cohen <philc@audyx.com>, dev@audyx.com
On Wed, Mar 11, 2015 at 10:12 AM, Raymond Toy <rtoy@google.com> wrote:

> This isn't really relevant to this list. It's not a support list.
> However, see below.
>
> On Wed, Mar 11, 2015 at 10:00 AM, Yehonathan Sharvit <viebel@gmail.com>
> wrote:
>
>> Hello Guys,
>>
>> I have a very tough issue to share with you.
>>
>> On a *specific Windows 7 machine*, the audioContext doesn’t progress.
>> It’s currentTime stays 0 forever.
>>
>> As a consequence, *start/stop/onended do not work*.
>>
>> Here is a js fiddle with the code of a reproduction of the bug.
>>
>> http://jsfiddle.net/6qfub5zd/11/
>>
>> The code is very simple:
>>
>> *c = new AudioContext;*
>> *o = c.createOscillator();*
>> *o.connect(c.destination);*
>> *o.onended = function() {alert("done");};*
>> *o.start();*
>> *o.stop();*
>>
>
> You start then stop the oscillator immediately.  It's likely the
> oscillator never actually started so onended never gets called.
>
> I'm sure if you examine the context, time has actually progressed because
> c.currentTime isn't 0.  If it is actually 0, please file a bug with your
> browser vendor.
>
>
>> *o.stop(c.currentTime + 0.5);*
>>
>
My mistake.  The second stop is also valid and is the actual value used if
the sound hasn't already been stopped.  So you have a race on whether the
first stop() stops the oscillator before the scond call to stop has been
executed.


> *setTimeout(function () {    alert("elpased: " + c.currentTime);}, 1000);*
>>
>>
>> On the mentioned machine,
>> 1. no sound is played
>> 2. the alert with “done” never appears.
>> 3. the elapsed time is: 0
>>
>>
>> Has someone  an idea about what could cause this kind of issues?
>>
>>
>> *System Specifications:*
>> *OS: Windows 7*
>> *CPU: Intel Core i3-2350M 2.30GHZ - 64bits*
>> *RAM: 4GB*
>>
>> Thanks,
>> Yehonathan;
>>
>
>
Received on Wednesday, 11 March 2015 17:20:30 UTC

This archive was generated by hypermail 2.3.1 : Wednesday, 11 March 2015 17:20:31 UTC