Kontakt VST3 cutting off long notes randomly when bouncing to audio???

EvilDragon said:

I've looked, and I couldn't see any code that would do this specifically for VST3 only... The actual voice processing code is plugin type agnostic and supports up to 16 threads.

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This is obvious speculation, but the Kontakt VST3 could have failed to cleanly enter bounce mode, making it subject to overload protection that's only supposed to operate in live mode. Setting bounce/offline mode is plugin-dependent functionality and is implemented quite differently between VST3 and VST2. The VST2 plugin explicitly asks the VST2 host about offline mode through a host callback, whereas the VST3 host supplies the VST3 plugin with the current offline state on every render call, and must be stored by the VST3 plugin between render calls.

I don't know the internals of Kontakt, but for clarity, there's no sign for us that a voice is dropped, but the audio just drops out from the disk-streaming portion being silent. The preloaded audio and release sample is still being presented.

Right so plugin abstraction is handled by a library which is handled by a separate team. That code is all gibberish to me.


EDIT: I can see offline processing mode is confirmed on every Process() call, though.

EvilDragon said:

EDIT: I can see offline processing mode is confirmed on every Process() call, though.

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The process() call is executed on the audio thread, whereas disk streaming is Kontakt’s custom background thread. Theoretically, the disk streaming and audio thread can be in disagreement about being in offline mode. The VST3 plugin must itself forward the offline flag from process() to the background thread.

That is being done.

EvilDragon said:

That is being done.

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That’s good to know.

Do you have access to a Kontakt development environment? If I write a host program that triggers the problem, can you debug it?

Yup I could try. DM

EvilDragon said:

Yup I could try. DM

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Excellent. Give me some time. It's unlikely that I will find the time this week.

I can detect the dropout and send a MIDI event to Kontakt for you to break at.

Interestingly, after some more testing I can't seem to replicate this in Logic, while in Cubase and Reaper it happens almost every time.

inthevoid said:

Interestingly, after some more testing I can't seem to replicate this in Logic, while in Cubase and Reaper it happens almost every time.

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Can I ask if you’re using the AU or the VST3 in Reaper?

Wallander said:

Can I ask if you’re using the AU or the VST3 in Reaper?

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The VST3 in Reaper! Happy to test with the AU version in Reaper this weekend

fwiw I have seen these dropout issues in both the AAX version and the AU version of kontakt. On my old system however if an instrument was displaying the bug reliably, I could load it into kontakt 5 and the problem would go away

Update: it does happen in Logic after all. Just had it with CSS and with Infinite Woodwind saxes.

inthevoid said:

Update: it does happen in Logic after all. Just had it with CSS and with Infinite Woodwind saxes.

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If you manually set "Offline (Bounce Mode)" in the engine tab of each Kontakt instance before bouncing, does the problem go away?

Wallander said:

If you manually set "Offline (Bounce Mode)" in the engine tab of each Kontakt instance before bouncing, does the problem go away?

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Will test this this evening!

Wallander said:

If you manually set "Offline (Bounce Mode)" in the engine tab of each Kontakt instance before bouncing, does the problem go away?

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Just tested - unfortunately no success - 3/3 test renders with a single instance of CSS 1st Violins playing a legato line had dropouts, even with the offline bounce mode active.

inthevoid said:

Just tested - unfortunately no success - 3/3 test renders with a single instance of CSS 1st Violins playing a legato line had dropouts, even with the offline bounce mode active.

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That's still interesting to know. Thanks for trying it.

Had a nice conversation with NI support. And yep -- confirmed everything in this thread, and confirmed there is no fix coming any time soon. Better set up print templates for online rendering Kontakt stems from here on out!

I found a fix for offline rendering mode sent from host not being respected, it's coming up in 7.6!

Everything works perfectly for us with Kontakt 7.6. No more dropouts. Great work!

EvilDragon said:

I found a fix for offline rendering mode sent from host not being respected, it's coming up in 7.6!

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Great work! I haven't had it in a while so I can't test - just to be sure - it's making the offline rendering mode workaround work reliably? Or a fix of the whole DFD/loop dropout issue?