servers [windows]: select WASAPI as default device if available by dyfer · Pull Request #6994 · supercollider/supercollider

dyfer · 2025-06-16T22:59:11Z

Purpose and Motivation

Use WASAPI for the default device selection on Windows.

We seem to need this before we can disable old APIs, see #6900 (comment)

Types of changes

New feature (?)

To-do list

Code is tested
All tests are passing
Updated documentation
This PR is ready for review

dyfer · 2025-06-16T23:00:49Z

@Spacechild1 how does this look to you?
My only concern is that apiInfo->default[In/Out]putDevice could theoretically return noPaDevice and I wonder if we should call Pa_GetDefault... when that happens?
ButPa_GetDefaultInputDevice()/Pa_GetDefaultOutputDevice() can also return noPaDevice so maybe this is an edge case anyway.

Spacechild1 · 2025-06-20T13:11:48Z

I don't have time to actually test myself, but looks good to me!

My only concern is that apiInfo->default[In/Out]putDevice could theoretically return noPaDevice and I wonder if we should call Pa_GetDefault... when that happens?

Actually, we should not do that because we might end up with two devices with different APIs. For example, take a laptop with no built-in microphone input, but a generic ASIO driver: GetPaDefaultDevice would return the ASIO driver as the input device and WASAPI speakers as the output device.

I'd suggest to add a comment to GetPaDefaultDevice and explain why we do not fall back to Pa_GetDefault[Input|Ouput]Device on noPaDevice.

if available

Spacechild1 · 2025-06-20T20:55:39Z

I just tried this locally. From my side side this is good to go!

dyfer · 2025-06-20T21:13:56Z

Thanks @Spacechild1
Do you think we should push it to 3.14.0 or 3.14.1 ? I thought that maybe it would be nice to introduce this default in a release so that it's widely tested, before we go ahead and remove old APIs (which could happen in 3.15).
But maybe there's no rush...

Spacechild1 · 2025-06-20T21:19:27Z

I think this can definitely go to 3.14. I would rather not do this in a bug fix release.

dyfer · 2025-06-20T21:26:29Z

I would rather not do this in a bug fix release.

Do you mean - yes in 3.14.0 but not in 3.14.1 ?

Spacechild1 · 2025-06-20T21:29:23Z

Yes!

capital-G · 2025-06-20T21:31:01Z

if this goes into 3.14 we definitely need a 3.14-rc2

dyfer · 2025-06-20T21:35:20Z

Yes, we need rc2 anyway, I think.
I think it would be good to have this in, despite it not being technically a bugfix from rc1, as this really is the desired behavior on Windows (unless some terrible incompatibility emerges in wider testing...)

BTW this wasn't feasible until Christof's relatively recent PR to enable resampling in WASAPI, that's why we haven't had this for so long.

capital-G · 2025-06-20T21:56:05Z

I don't have any clue about windows anymore, but if it helps and is not a big change I think its fine to bring this into 3.14 via rc2 ;)

dyfer · 2025-06-20T22:09:51Z

All right! In that case I'll merge this.

dyfer · 2025-06-20T22:12:36Z

To be extra safe:
@prko @sternsc would you be able to test a build from this PR on your Windows systems? Boot the server with a default device and make sure the sound works fine? Thanks!

prko · 2025-06-21T00:38:00Z

Here are two results:

Windows 11 ARM:

Booting server 'localhost' on address 127.0.0.1:57110.

Device options:
- MME : Microsoft Sound Mapper - Input
  (2 ins, 0 outs)
- MME : Microphone (High Definition Aud
  (2 ins, 0 outs)
- MME : Microsoft Sound Mapper - Output
  (0 ins, 2 outs)
- MME : Speakers (High Definition Audio
  (0 ins, 8 outs)
- Windows DirectSound : Primary Sound Capture Driver
  (2 ins, 0 outs)
- Windows DirectSound : Microphone (High Definition Audio Device)
  (2 ins, 0 outs)
- Windows DirectSound : Primary Sound Driver
  (0 ins, 2 outs)
- Windows DirectSound : Speakers (High Definition Audio Device)
  (0 ins, 8 outs)
- Windows WASAPI : Speakers (High Definition Audio Device)
  (0 ins, 2 outs)
- Windows WASAPI : Microphone (High Definition Audio Device)
  (2 ins, 0 outs)
- Windows WDM-KS : Microphone (HD Audio Microphone)
  (2 ins, 0 outs)
- Windows WDM-KS : Speakers (HD Audio Speaker)
  (0 ins, 8 outs)

Requested devices:
  In:
  - (default)
  Out:
  - (default)

Selecting default system input/output devices

Booting with:
  In: Windows WASAPI : Microphone (High Definition Audio Device)
  Out: Windows WASAPI : Speakers (High Definition Audio Device)
  Sample rate: 48000.000
  Latency (in/out): 0.022 / 0.024 sec
SC_AudioDriver: sample rate = 48000.000000, driver's block size = 64
SuperCollider 3 server ready.
Requested notification messages from server 'localhost'
localhost: server process's maxLogins (1) matches with my options.
localhost: keeping clientID (0) as confirmed by server process.
Shared memory server interface initialized

Windows 10 ARM:


Device options:
- MME : Microsoft Sound Mapper - Input
  (2 ins, 0 outs)
- MME : Microphone (High Definition Aud
  (2 ins, 0 outs)
- MME : Microsoft Sound Mapper - Output
  (0 ins, 2 outs)
- MME : Speakers (High Definition Audio
  (0 ins, 8 outs)
- Windows DirectSound : Primary Sound Capture Driver
  (2 ins, 0 outs)
- Windows DirectSound : Microphone (High Definition Audio Device)
  (2 ins, 0 outs)
- Windows DirectSound : Primary Sound Driver
  (0 ins, 2 outs)
- Windows DirectSound : Speakers (High Definition Audio Device)
  (0 ins, 8 outs)
- Windows WASAPI : Speakers (High Definition Audio Device)
  (0 ins, 2 outs)
- Windows WASAPI : Microphone (High Definition Audio Device)
  (2 ins, 0 outs)
- Windows WDM-KS : Microphone (HD Audio Microphone)
  (2 ins, 0 outs)
- Windows WDM-KS : Speakers (HD Audio Speaker)
  (0 ins, 8 outs)

Requested devices:
  In:
  - (default)
  Out:
  - (default)

Selecting default system input/output devices

Booting with:
  In: Windows WASAPI : Microphone (High Definition Audio Device)
  Out: Windows WASAPI : Speakers (High Definition Audio Device)
  Sample rate: 48000.000
  Latency (in/out): 0.022 / 0.024 sec
SC_AudioDriver: sample rate = 48000.000000, driver's block size = 64
SuperCollider 3 server ready.
Requested notification messages from server 'localhost'
localhost: server process's maxLogins (1) matches with my options.
localhost: keeping clientID (0) as confirmed by server process.
Shared memory server interface initialized

prko · 2025-06-22T10:09:33Z

I have tested with Windows 10 (x64) and Windows 11 (64) on Parallels Desktop on iMac 2013 (intel i7).
The test results are successful as above.

Windows 10 (x64)

Booting server 'localhost' on address 127.0.0.1:57110.

Device options:
- MME : Microsoft Sound Mapper - Input
  (2 ins, 0 outs)
- MME : Microphone (High Definition Aud
  (2 ins, 0 outs)
- MME : Microsoft Sound Mapper - Output
  (0 ins, 2 outs)
- MME : Speakers (High Definition Audio
  (0 ins, 8 outs)
- Windows DirectSound : Primary Sound Capture Driver
  (2 ins, 0 outs)
- Windows DirectSound : Microphone (High Definition Audio Device)
  (2 ins, 0 outs)
- Windows DirectSound : Primary Sound Driver
  (0 ins, 2 outs)
- Windows DirectSound : Speakers (High Definition Audio Device)
  (0 ins, 8 outs)
- Windows WASAPI : Speakers (High Definition Audio Device)
  (0 ins, 2 outs)
- Windows WASAPI : Microphone (High Definition Audio Device)
  (2 ins, 0 outs)
- Windows WDM-KS : Speakers (HD Audio Speaker)
  (0 ins, 8 outs)
- Windows WDM-KS : Microphone (HD Audio Microphone)
  (2 ins, 0 outs)

Requested devices:
  In:
  - (default)
  Out:
  - (default)

Selecting default system input/output devices

Booting with:
  In: Windows WASAPI : Microphone (High Definition Audio Device)
  Out: Windows WASAPI : Speakers (High Definition Audio Device)
  Sample rate: 48000.000
  Latency (in/out): 0.022 / 0.024 sec
SC_AudioDriver: sample rate = 48000.000000, driver's block size = 64
SuperCollider 3 server ready.
Requested notification messages from server 'localhost'
localhost: server process's maxLogins (1) matches with my options.
localhost: keeping clientID (0) as confirmed by server process.
Requested notification messages from server 'localhost'
/notify : already registered
localhost - already registered with clientID 0.
localhost - handling login request though already registered - 
This seems to be a login after a loss of network contact - 
- reconnected with the same clientID as before, so probably all is well.

Shared memory server interface initialized

Windows 11 (x64)

Booting server 'localhost' on address 127.0.0.1:57110.

Device options:
- MME : Microsoft Sound Mapper - Input
  (2 ins, 0 outs)
- MME : Microphone (High Definition Aud
  (2 ins, 0 outs)
- MME : Microsoft Sound Mapper - Output
  (0 ins, 2 outs)
- MME : 스피커 (High Definition Audio Devi
  (0 ins, 8 outs)
- Windows DirectSound : Primary Sound Capture Driver
  (2 ins, 0 outs)
- Windows DirectSound : Microphone (High Definition Audio Device)
  (2 ins, 0 outs)
- Windows DirectSound : Primary Sound Driver
  (0 ins, 2 outs)
- Windows DirectSound : 스피커 (High Definition Audio Device)
  (0 ins, 8 outs)
- ASIO : ASIO4ALL v2
  (2 ins, 8 outs)
- ASIO : Generic Low Latency ASIO Driver
  (2 ins, 2 outs)
- Windows WASAPI : 스피커 (High Definition Audio Device)
  (0 ins, 2 outs)
- Windows WASAPI : Microphone (High Definition Audio Device)
  (2 ins, 0 outs)
- Windows WDM-KS : Speakers (HD Audio Speaker)
  (0 ins, 8 outs)
- Windows WDM-KS : Microphone (HD Audio Microphone)
  (2 ins, 0 outs)

Requested devices:
  In:
  - (default)
  Out:
  - (default)

Selecting default system input/output devices

Booting with:
  In: Windows WASAPI : Microphone (High Definition Audio Device)
  Out: Windows WASAPI : 스피커 (High Definition Audio Device)
  Sample rate: 48000.000
  Latency (in/out): 0.022 / 0.024 sec
SC_AudioDriver: sample rate = 48000.000000, driver's block size = 64
SuperCollider 3 server ready.
Requested notification messages from server 'localhost'
localhost: server process's maxLogins (1) matches with my options.
localhost: keeping clientID (0) as confirmed by server process.
Shared memory server interface initialized

dyfer · 2025-06-23T19:47:04Z

@prko did you try playing sound in your tests by any chance? Does it work fine with now dropouts etc (comparing to the MME driver)?

sternsc · 2025-06-23T20:02:29Z

The device in question is input-only, like a microphone, and that seemed to work fine. From: Marcin Pączkowski ***@***.***> Sent: Monday, 23 June 2025 21:47 To: supercollider/supercollider ***@***.***> Cc: sternsc ***@***.***>; Mention ***@***.***> Subject: Re: [supercollider/supercollider] servers [windows]: select WASAPI as default device if available (PR #6994) [Image removed by sender.]dyfer left a comment (supercollider/supercollider#6994)<#6994 (comment)> @prko<https://github.com/prko> did you try playing sound in your tests by any chance? Does it work fine with now dropouts etc (comparing to the MME driver)? — Reply to this email directly, view it on GitHub<#6994 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AAXQZNE7EKCDIA5OEIQ54CL3FBKU5AVCNFSM6AAAAAB7OSOKLGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDSOJXG42DSOBTGA>. You are receiving this because you were mentioned.Message ID: ***@***.***>

prko · 2025-06-23T21:42:36Z

The following is a result on a real machine:

Windows 10 x64:

Booting server 'localhost' on address 127.0.0.1:57110.

Device options:
- MME : Microsoft Sound Mapper - Input
  (2 ins, 0 outs)
- MME : Microphone (Realtek High Defini
  (2 ins, 0 outs)
- MME : Microsoft Sound Mapper - Output
  (0 ins, 2 outs)
- MME : Speakers (Realtek High Definiti
  (0 ins, 2 outs)
- Windows DirectSound : Primary Sound Capture Driver
  (2 ins, 0 outs)
- Windows DirectSound : Microphone (Realtek High Definition Audio)
  (2 ins, 0 outs)
- Windows DirectSound : Primary Sound Driver
  (0 ins, 2 outs)
- Windows DirectSound : Speakers (Realtek High Definition Audio)
  (0 ins, 2 outs)
- Windows WASAPI : Speakers (Realtek High Definition Audio)
  (0 ins, 2 outs)
- Windows WASAPI : Microphone (Realtek High Definition Audio)
  (2 ins, 0 outs)
- Windows WDM-KS : Speakers (Realtek HD Audio output)
  (0 ins, 2 outs)
- Windows WDM-KS : Stereo Mix (Realtek HD Audio Stereo input)
  (2 ins, 0 outs)
- Windows WDM-KS : Microphone (Realtek HD Audio Mic input)
  (2 ins, 0 outs)
- Windows WDM-KS : Microphone (Parallels Access Sound Waveout)
  (2 ins, 0 outs)
- Windows WDM-KS : Speakers (Parallels Access Sound Waveout)
  (0 ins, 2 outs)

Requested devices:
  In:
  - (default)
  Out:
  - (default)

Selecting default system input/output devices

Booting with:
  In: Windows WASAPI : Microphone (Realtek High Definition Audio)
  Out: Windows WASAPI : Speakers (Realtek High Definition Audio)
  Sample rate: 48000.000
  Latency (in/out): 0.022 / 0.023 sec
SC_AudioDriver: sample rate = 48000.000000, driver's block size = 64
SuperCollider 3 server ready.
Requested notification messages from server 'localhost'
localhost: server process's maxLogins (1) matches with my options.
localhost: keeping clientID (0) as confirmed by server process.
Shared memory server interface initialized

I tested the following code firestly:

(
// Dust randomly triggers Decay to create an exponential
// decay envelope for the WhiteNoise input source
{
z = Decay.ar(Dust.ar(1, 0.5), 0.3, WhiteNoise.ar);
DelayC.ar(z, 0.2, 0.2, 1, z); // input is mixed with delay via the add input
}.play
)

It was successful.
Then I tested the following code after freeing the sound process above:

(
{
	z = SoundIn.ar(0);
	DelayC.ar([z, 0], 2, SinOsc.ar(1/60), 0.1, [0, z]); // input is mixed with delay via the add input
}.play
)

Although I could see the sound level on the s.meter, I could not hear any sound.
I quit the server and the interpreter. After starting Sclang and booting the server, everything worked.

There are no dropouts on this real machine:

Processor Intel(R) Core(TM) i3-3220T CPU @ 2.80GHz 2.80 GHz
Installed RAM 8.00 GB (7.89 GB usable)
Storage 932 GB SSD Samsung SSD 870 EVO 1TB
Graphics Card Intel(R) HD Graphics (32 MB)
System Type 64-bit operating system, x64-based processor
Pen and touch No pen or touch input is available for this display

dyfer · 2025-06-23T23:56:30Z

Thanks for testing @prko !

dyfer · 2025-06-23T23:57:21Z

After additional testing I'm now merging this, so that we include it in 3.14.0-rc2.

prko · 2025-06-24T00:18:11Z

Sorry for the delay in the sound test. On the virtual machine, there are always dropouts, so I could not test the sound on my MacBook Pro.

dyfer · 2025-06-24T01:08:06Z

Thanks! But are the dropouts worse than when using a MME device?
(I also found a VM to have dropouts typically)

prko · 2025-06-24T14:50:25Z

I think WASAPI drops more sound.
tested with http://sccode.org/1-5al

Spacechild1 · 2025-06-25T11:34:58Z

I think WASAPI drops more sound.

That's not surprising, given that MME's default output latency is 4x larger than WASAPI's (92 ms vs 23 ms). On an actual Windows machine, you shouldn't get any dropouts in either case. (23 ms is still a pretty big buffer size.) Your other test confirmed this.

As @dyfer already noted, VMs are known for having audio issues. If you experience dropouts, just increase the hardware buffer size. (4096 roughly matches the MME default.)

sternsc · 2025-06-26T12:52:32Z

@dyfer Sorry for the delay; I have now tried the PR "3.15.0-dev" on Win10 and Win11, with a startup file that doesn't specify anything audio. On booting the server, all the APIs are still listed, and it selects WASAPI on the default audio device(s). This is as intended, I believe. Good!

…ider#6994)" This reverts commit b390407.

dyfer · 2025-07-16T19:06:37Z

My only concern is that apiInfo->default[In/Out]putDevice could theoretically return noPaDevice and I wonder if we should call Pa_GetDefault... when that happens?

Actually, we should not do that because we might end up with two devices with different APIs. For example, take a laptop with no built-in microphone input, but a generic ASIO driver: GetPaDefaultDevice would return the ASIO driver as the input device and WASAPI speakers as the output device.

I'd suggest to add a comment to GetPaDefaultDevice and explain why we do not fall back to Pa_GetDefault[Input|Ouput]Device on noPaDevice.

@Spacechild1 from a test in CI I believe this is not correct after all.

When running the current version on a system with only an ASIO device, the server now doesn't select ASIO as the default device (presumably because we get noPaDevice) and doesn't boot: https://github.com/supercollider/supercollider/actions/runs/16325805905/job/46116611466#step:6:230

Separately we have logic to handle different APIs, so I think we should always return a default device from the GetPaDefaultDevice function. I tried this on the windows tests PR and the tests now seem to run.

I think we need to fix this for 3.14 and make rc3, what do you think?

EDIT: fix submitted in #7051

dyfer added comp: scsynth comp: supernova os: Windows labels Jun 16, 2025

dyfer force-pushed the topic/select-wasapi-Windows branch 2 times, most recently from 382d172 to 3ac4c94 Compare June 17, 2025 17:42

servers [windows]: select WASAPI as default device

4dc5415

if available

dyfer force-pushed the topic/select-wasapi-Windows branch from 3ac4c94 to 4dc5415 Compare June 20, 2025 17:00

Spacechild1 self-requested a review June 20, 2025 20:55

Spacechild1 approved these changes Jun 20, 2025

View reviewed changes

Spacechild1 mentioned this pull request Jun 20, 2025

Disable obsolete audio APIs on Windows #6900

Merged

4 tasks

dyfer changed the base branch from develop to 3.14 June 20, 2025 21:26

dyfer merged commit b390407 into supercollider:3.14 Jun 23, 2025
25 checks passed

Spacechild1 mentioned this pull request Jul 13, 2025

No audio on Windows 11: "error opening audio: Unanticipated host error" pure-data/pure-data#2578

Open

dyfer added a commit to dyfer/supercollider that referenced this pull request Jul 16, 2025

Revert "servers [windows]: select WASAPI as default device (supercoll…

1765197

…ider#6994)" This reverts commit b390407.

dyfer mentioned this pull request Jul 16, 2025

Fix default device selection on Windows when no WASAPI devices are available #7051

Merged

3 tasks

Conversation

dyfer commented Jun 16, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Purpose and Motivation

Types of changes

To-do list

Uh oh!

dyfer commented Jun 16, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Spacechild1 commented Jun 20, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Spacechild1 commented Jun 20, 2025

Uh oh!

dyfer commented Jun 20, 2025

Uh oh!

Spacechild1 commented Jun 20, 2025

Uh oh!

dyfer commented Jun 20, 2025

Uh oh!

Spacechild1 commented Jun 20, 2025

Uh oh!

capital-G commented Jun 20, 2025

Uh oh!

dyfer commented Jun 20, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

capital-G commented Jun 20, 2025

Uh oh!

dyfer commented Jun 20, 2025

Uh oh!

dyfer commented Jun 20, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

prko commented Jun 21, 2025

Uh oh!

prko commented Jun 22, 2025

Uh oh!

dyfer commented Jun 23, 2025

Uh oh!

sternsc commented Jun 23, 2025 via email

Uh oh!

prko commented Jun 23, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

dyfer commented Jun 23, 2025

Uh oh!

dyfer commented Jun 23, 2025

Uh oh!

Uh oh!

prko commented Jun 24, 2025

Uh oh!

dyfer commented Jun 24, 2025

Uh oh!

prko commented Jun 24, 2025

Uh oh!

Spacechild1 commented Jun 25, 2025

Uh oh!

sternsc commented Jun 26, 2025

Uh oh!

dyfer commented Jul 16, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

5 participants

dyfer commented Jun 16, 2025 •

edited

Loading

dyfer commented Jun 16, 2025 •

edited

Loading

Spacechild1 commented Jun 20, 2025 •

edited

Loading

dyfer commented Jun 20, 2025 •

edited

Loading

dyfer commented Jun 20, 2025 •

edited

Loading

prko commented Jun 23, 2025 •

edited

Loading

dyfer commented Jul 16, 2025 •

edited

Loading