[Portaudio] Distortion in WASAPI exclusive mode

[Erik Ronström]

Hi List,

I’m getting serious distortion when using WASAPI exclusive mode, while shared mode sounds fine. This seems to be regardless of buffer size and suggested latency. Anyone recognizes this?

It may of course be that I don’t provide audio data fast enough, but it seems strange to me that I have no problems with shared mode. I would have thought that exclusive mode would be more stable, compared with shared mode with the same settings.

Erik

[Chris]

No problem with WASAPI in exclusive mode here.


-----Original Message-----
From: Erik Ronström <***@doremir.com>
To: portaudio list <***@lists.columbia.edu>
Sent: Fri, Apr 8, 2016 2:33 am
Subject: [Portaudio] Distortion in WASAPI exclusive mode


Hi List,


I’m getting serious distortion when using WASAPI exclusive mode, while shared mode sounds fine. This seems to be regardless of buffer size and suggested latency. Anyone recognizes this?


It may of course be that I don’t provide audio data fast enough, but it seems strange to me that I have no problems with shared mode. I would have thought that exclusive mode would be more stable, compared with shared mode with the same settings.


Erik

[Erik Ronström]

Hi again,

(answering myself for future reference, if someone else is having the same problem)

Further investigation shows that the problem only arises when using an input device – even if the sound from the input is not sent to the output. It seems like the problem is triggered by a combination of the following factors:

- WASAPI
- event-mode (as opposed to polling mode)
- exclusive mode
- stream has an input

Since others have been having the same problem, it seems like this may be a bug in WASAPI, or at least an incompatibility between WASAPI and certain drivers and/or hardware. Thus, it may not be a Portaudio problem.

Still, it is extremely annoying


Erik

Post by Erik Ronström
Hi List,
I’m getting serious distortion when using WASAPI exclusive mode, while shared mode sounds fine. This seems to be regardless of buffer size and suggested latency. Anyone recognizes this?
It may of course be that I don’t provide audio data fast enough, but it seems strange to me that I have no problems with shared mode. I would have thought that exclusive mode would be more stable, compared with shared mode with the same settings.
Erik

[Chris]

What kind of input device are you using? Do you have another one you could try?

I wouldn't rule out the drivers at all.


-----Original Message-----
From: Erik Ronström <***@doremir.com>
To: portaudio list <***@lists.columbia.edu>
Sent: Wed, Apr 20, 2016 1:44 am
Subject: Re: [Portaudio] Distortion in WASAPI exclusive mode


Hi again,


(answering myself for future reference, if someone else is having the same problem)



Further investigation shows that the problem only arises when using an input device – even if the sound from the input is not sent to the output. It seems like the problem is triggered by a combination of the following factors:


- WASAPI
- event-mode (as opposed to polling mode)
- exclusive mode
- stream has an input


Since others have been having the same problem, it seems like this may be a bug in WASAPI, or at least an incompatibility between WASAPI and certain drivers and/or hardware. Thus, it may not be a Portaudio problem.


Still, it is extremely annoying…


Erik







8 apr 2016 kl. 11:33 skrev Erik Ronström <***@doremir.com>:


Hi List,


I’m getting serious distortion when using WASAPI exclusive mode, while shared mode sounds fine. This seems to be regardless of buffer size and suggested latency. Anyone recognizes this?


It may of course be that I don’t provide audio data fast enough, but it seems strange to me that I have no problems with shared mode. I would have thought that exclusive mode would be more stable, compared with shared mode with the same settings.


Erik









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