24 Jul
2010
24 Jul
'10
11:54 p.m.
As usual, the nature of the problem becomes clearer
immediately after I form my question and post it.
So let me re-phrase the problem and question:
I think these issues are part of a more general
bug with ALSA + envy24.
ALSA is not able to change the envy24's sample rate.
This requires the user to manually set the rate in the
envy24control mixer before starting any ALSA based app.
With Flash, it is simply playing through ALSA using
whatever the default ALSA sample rate is.
In this case that's 48000Hz, (or so each *believes*).
But the true rate is set by the envy24control mixer
which by default is 41000Hz.
Thus when playing Flash videos, the audio is the wrong
pitch and too slow.
I now recall Amarok has the same problem.
And certainly, when starting Jack with the ALSA back end, I must
set Jack's sample rate to match envy24control's sample rate.
Otherwise the audio is wrong.
So the solution is one of the following:
1) Fix the bug. ALSA should change the envy24's sample rate.
2) Change the default ALSA sample rate to 44100Hz. (How to do that??)
3) Do it on an app by app basis setting each app's sample rate
to match envy24's rate.
The original question is still valid though - even if the bug was fixed
and ALSA was able to set envy24 to 48000Hz when starting Flash,
what if I want to play Flash videos at 44100Hz? How to do that?
These issues may have been fixed in the year or so since my
current distro. Must check.
Thanks again. Tim.
On July 24, 2010 03:54:19 pm Tim E. Real wrote:
Hello.
Just a follow up to something I said a while back.
I think Gene H. was saying he couldn't get audio
and I had replied that I disabled Pulse and it
appeared to be working.
But even after disabling Pulse, sometimes I still was
not getting audio in Flash on YouBoob etc.
When I did have audio, I noticed that every video's
audio seemed slower and lower in pitch.
I was fooled into thinking that the owners of the
videos had somehow remixed them at lower
pitches or something.
It turns out that Flash wants to play everything
at a 48000Hz sample rate.
Since my audio card is an Envy24 based card,
it always boots up in 44100Hz sample rate mode.
So now, before I play Flash videos, I must open the
envy24control mixer and set the sample rate to 48000Hz.
It works every time now !
Can someone explain the process of how Flash plays audio,
and how to force it to use 44100Hz?
I'm confused because at 44100Hz the audio is in sync
with the video, yet it is lower in pitch and slower.
Does this mean Flash is really playing the video slower?
Thanks. Tim.
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