Issues with build #24496 (May 8th 2026)

[Alex/AT]

Let's start with something...

No So Yasapi output stopped working in this build. Windows 11, Creative AE-9. Tried push/pull, shared/exclusive to no avail.

Playback just skips tracks without any sound. Stop 'hangs' for several seconds, then either stops or just continues skipping tracks. Sometimes (once in a couple of start/stops it either shows buffer playback loop condition (same small piece repeating without updating), or plays one track then returns to the above behavior.

Downgrading out_notsoyasapi.dll to the one from build #20202 (not exactly specific bugless version, maybe some later ones also work, but this is just the one I have archived) immediately makes it work. If there's a way to download older builds, I can easily test each one to find in which build exactly it stops working).

[dro]

Is this the x86 or x64 build of wacup? Does notsodirect work (am not interested in the wasapi vs directsound view point, just if playback works with it).

[Alex/AT]

x86 specifically. I also tested x64 indeed, but it exhibits the same behavior.

Yes, other output plugins all work. Just WASAPI one is bugged. WASAPI one does not work when passed through Neo Mixer plugin either.

[Alex/AT]

Failing version of plugin also reports strange buffer usage (see the attachment). Ring buffer is filled just a little, and shared buffer is not filled. And this is static - it does not change at all. It seems playback thread either hangs or aborts somewhere (may be wrong of course, no knowledge about the internals ).

[dro]

Until I can look into it (maybe the weekend but more likely next week at the earliest) I don't have any obvious reason as to why it'd be broken when it was seemingly working ok with 24472 when trying to figure out the notsodirect playback issues where a fix needed fixing with that build (which post-release updates or 24496 fixed).

If there's a way to download older builds, I can easily test each one to find in which build exactly it stops working).

The preview build download pages have a "prior preview build" section at the top for getting the prior ones.

I've also updated the known issues for 24496 (am not going to go further back) to indicate this & reports of the asio output plug-in not working in all setups.

Also has it been crashing for you during any of this?

[Alex/AT]

There are some crashes sometimes when I try to enter YASAPI configuration page by clicking on plugin from Output page.
If I enter it from the Output menu at the left, no crashes happen.

Plugin test result:
#24496, #24472, #24360, #23960, #23528, #23410, #23234 (DLL size 52224) - not working
#22982, #22656, #22626, #22278, #22222, #22022, #21640, #21622 (DLL size 51712) - not working
#21136, #21102 (DLL size 52736, same as in 20202) - NOT working
#20202 (DLL size 52736) - WORKING
#20088, #19994, #19516, #19100 (DLL size 52736, same as in 20202) - working
#17040 (DLL size 49664) - working

That's based on just specific .dll version testing in #24496 (replacing the DLL with DLL from build being tested).

To make sure it's not dependent on some API/ABI, I also tested #23234, #22982, #21622, #21136, #21102 as portable builds.
None are working properly, although #21136 and #21102 seem to work in Push mode (I normally tested Exclusive/Pull).

So obviously something happened between #20202 and #21102 there. It's kind of strange given DLL seems to be the same between 20202 and 21136/21102 though. Other video/audio players (AIMP, MPC-HC) work in Exclusive/Pull(Event) mode just fine.

[Alex/AT]

Any chances there is some debug logging that can be enabled to see what happens during YASAPI inner workings maybe?

[Alex/AT]

Some more information: push mode seems to work sometimes, but it needs few WACUP restarts to happen so.
If pull mode is used (pull never works), and then changed to push and back instead, push also never works.
If push is working after WACUP restart, it continues working until closed. Changing to pull once fails it until next working restart.
So it seems to be a matter of some timing issue / deadlock / stale lock / handle loss happening somewhere at initialization or close to it.

[dro]

The plug-in is a mess from assuming that what it was forked from actually worked but pull mode has never worked for me & there's no debugging modes with the plug-in. I do not like shipping such code when it's mostly never going to be used vs bloating the code base along with most of the time being a pain to figure out what should even be done for that side of things. All I know is that I managed to briefly try the plug-in with its default config yesterday & it worked without issue & having not intentionally messed with the plug-in in months I don't have a solution for why it's buggered & if it's going back to 20202 then that's a few years back. So until I can actually look at what code changed back then there's nothing I can do & no point you spending more time on it.