Solved - Student patch that crashes VCV's audio system

Never seen this before… a student made a fairly large FM patch. The assignment was to create one patch containing two DX7 algorithms – i.e., 12 FM-OPs in total, in two sections, with mixers as needed.

When I open the patch, VCV remains responsive – I can use all the menu options and edit the patch freely. But the audio is completely shut off, and modules are not performing any graphics updates (for instance, ADSRs display nothing, and you can’t see the moving circle showing where in the envelope you are). Engine > Performance meters show 0.0% for all modules.

I’m attaching an edited version where I tried to remove unused modules, and fixed a couple of connections. But I just cannot make this patch run, hence can’t grade it by sound.

log.txt doesn’t seem to have anything interesting, except maybe that the student was using Bogaudio plugins 2.3.43 but I’m on 2.4.44.


1114-015-018-c.vcv (3.8 KB)

Thanks. hjh

This sounds like what happens when you load a patch and the audio device that was previously being used is no longer available.

If you find the VCV audio module and set the device correctly for your system does that make the patch work?

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You are not describing a crash but rather modules not doing anything. Basic question: Have you selected a functional audio device in the audio module? And is the audio module fully connected? In Rack v2 the audio module is driving the whole patch, without a functioning one nothing happens in a patch.

… beat me by 5 seconds :slight_smile:

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Ah, I spotted the problem. I opened your patch and got your mysterious problem as well, nothing working. Then I zoomed the patch out completely and all the way over to the right you have an extra free floating audio module. Removing that fixed everything :slight_smile:

I am inclined to say that that’s a minor Rack bug and I wouldn’t expect it to behave like that, but there you go…



Could you change the title of this post to more accurately reflect what it’s about?

Dangit… I told the students repeatedly, “do not add more than one audio module, always use a mixer” but some of the students are rather sloppy, even late in the term.

Thanks for finding that.


I use VCV in class too and when I read your question I was almost sure this was the issue lol. Half the time they called me because it was not workimg it was that, and almost all the other cases were because they close the filter all the way… VCV is a brilliant piece of software to teach synthesis, realy I love it and it works perfectly for that purpose…

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