Just gone through hell for a WEIRD problem! Is this a BUG? Bakers should read this!

[pulsewalk]

Alright, so I'm working on a project, trying to clean it up from like 150 tracks, so I can reduce to maybe a 100. So I'm freezing tracks to make it lighter on the CPU, trying to put smaller clips from several tracks and gather them on the same track and so forth, anything to reduce the number of tracks.

And then suddenly I get to a point when I get a dropout every time I play past a certain point in the project! I just cannot understand what it is. The audio clicks and pops harshly, and playback is halted! Every single time I play it over a certain point.  And then when I try to play the track, it just keeps clicking and popping no matter where I put the play cursor, no audio more than harsh clicks and pops. So then, I either I have to restart the whole thing, or if I'm lucky, I can change the buffer settings for my audio driver (so the settings are reset that way), press the panic button in Cakewalk, and with some luck I'm able to play again (works sometimes, but sometimes don't and I have to restart everything). But no matter what I do, I cannot play through a certain point in the project! It's just stops right there!

I can play before that certain point, and I can play after it if I "jump over" it, but I can never play through it without the audio just going dead with clicks and pops.

So I decide to go track by track and finally I find the track which causes the problem. It's just a simple audio file. The thing is, I even bounced it out to another track in case the source track was corrupted somehow, with no luck. Even the bounced track caused the audio to stop working in Cakewalk.

Finally, I zoom in on the waveform and find the corruption in the attached image (circled with red).

Can you see the waveform dipping like a huge square? I have no idea where that come from, but it was NOT there before. I was most certain it got there when I chose to freeze the track! So I've done some tests and this is what I came up with:

1. It is the freezing that causes it. The original waveform, before freeze does NOT look like that! Look at the attached image, circled with green.
2. If I unfreeze it, it goes back to normal, fully playable.
3. If I freeze it again, the waveform gets corrupted again, not playable through the corrupted point.
4. If unfrozen again, it both look fine and is fully playable.
5. If I open the file in Wavelab, directly from Cakewalk, the error is shown in Wavelab too, BUT it plays just fine in Wavelab!
6. If I save the corrupt file in Wavelab, it shows up just fine when I open it again (no corruption shown) and it plays fine in Winamp too. If I open up this same file in Cakewalk, it shows up fine again without corruption. With other words, saving it in Wavelab seem to automatically correct the problem.

I might add, that this have happened to me lots of times before, and each time I almost pulled out all my hair because I could never find the culprit. Every time I had to revert to an earlier version to be able to work the project again, resulting in having to redo a lot of work. Now, I know better.

So what is this and why is Cakewalk so very sensitive to this when Wavelab just ignores this corruption? And why is the freeze corrupting the waveform at all?

Edited November 6, 2023 by pulsewalk

[David Baay]

31 minutes ago, pulsewalk said:

It is the freezing that causes it. The original waveform, before freeze does NOT look like that!

Highly likely a misbehaving plugin. What's on the track?

[Bristol_Jonesey]

What happens if you bounce this to a new track and freeze that one?

[Wookiee]

@pulsewalk does the track have FX plugins? If so I would disabled one at a time and try bouncing. If it dissappears you have your answer. People always blame the host before checking the alternatives.

[pulsewalk]

9 hours ago, David Baay said:

Highly likely a misbehaving plugin. What's on the track?

 

7 hours ago, Bristol_Jonesey said:

What happens if you bounce this to a new track and freeze that one?

 

7 hours ago, Wookiee said:

@pulsewalk does the track have FX plugins? If so I would disabled one at a time and try bouncing. If it dissappears you have your answer. People always blame the host before checking the alternatives.

@David Baay & @Wookiee Indeed it was! It's Fabfilter Simplon. Disabling it took care of the problem!

@Bristol_Jonesey Can't do that any more. Yesterday I could bounce tracks, even though the bouncing function gave me the wrong results. Today, I cannot bounce at all. I'm writing about exactly this in another thread right now. However, when I disable the FX plugin Fabfilter Simplon, this wave corruption will not happen.

 

Edited November 6, 2023 by pulsewalk

[pulsewalk]

Update:

I cannot figure this out.

1.

Copying the corrupted wave file  (the one with the red circle) into a new project in Cakewalk will actually allow to play through the clip, with a click/pop where the corruption is. But the audio engine seems to stay stable in this new project! The audio engine is only killed at that spot in the original project file.

 

2.

The above fact makes one think that it is the plugin itself that is causing the problem, not the waveform. But either disabling the plugin, turning of the FX plugin rack, or even deleting the Fabfilter Simplon entirely from the track, does not solve the issue with the audio engine dying when playing back the corrupt waveform in the original project!

With other words, the corrupted waveform will play through in a new clean project file, with only a click/pop where the corruption is, not disturbing the audio engine. While playing the same file in the original project will NOT play through,... it will kill the audio engine, no matter if I disable or even delete the plugin that seem to be causing this.

Kinda odd?

Edited November 6, 2023 by pulsewalk

[David Baay]

1 hour ago, pulsewalk said:

The above fact makes one think that it is the plugin itself that is causing the problem, not the waveform. But either disabling the plugin, turning of the FX plugin rack, or even deleting the Fabfilter Simplon entirely from the track, does not solve the issue with the audio engine dying when playing back the corrupt waveform in the original project!

The plugin is already disabled by freezing the track. My guess would be there's something else going on in the project coincidentally at the same point that's causing the problem. Try archiving the track to check that.

In the past, I have seen these kind of amplitude spikes happening in real time with specific plugins applied to dynamically stretched audio with the 64-bit Double-Precision Engine. My first inclination when seeing any kind of plugin misbehavior is to try disabling 64-bit DPE and see if the problem goes away. And if any of the audio is being stretched, you might want to consider rendering it by Bounce to Clips(s).

Also, some "Goldilocks" FX don't play nice when rendering offline at very low or very high buffer sizes. You can set an intermediate value for BounceBufSizeMsec in Preferences > Audio > Configuration File (AUD.INI) to override the realtime ASIO buffer setting that's used by default for offline rendering. I've had mine set to 20 (milliseconds) for years without an issue, but if the plugin is having trouble with a larger buffer size, you might want to try something on the order 10ms (480 samples at 48kHz).

[Wookiee]

@pulsewalk the only thing that comes to mind is that the plugin corrupted the project in much deeper ways than is obvious, PITA I realise but unfortunately it happens. 

[pulsewalk]

4 hours ago, David Baay said:

The plugin is already disabled by freezing the track. My guess would be there's something else going on in the project coincidentally at the same point that's causing the problem. Try archiving the track to check that.

In the past, I have seen these kind of amplitude spikes happening in real time with specific plugins applied to dynamically stretched audio with the 64-bit Double-Precision Engine. My first inclination when seeing any kind of plugin misbehavior is to try disabling 64-bit DPE and see if the problem goes away. And if any of the audio is being stretched, you might want to consider rendering it by Bounce to Clips(s).

Also, some "Goldilocks" FX don't play nice when rendering offline at very low or very high buffer sizes. You can set an intermediate value for BounceBufSizeMsec in Preferences > Audio > Configuration File (AUD.INI) to override the realtime ASIO buffer setting that's used by default for offline rendering. I've had mine set to 20 (milliseconds) for years without an issue, but if the plugin is having trouble with a larger buffer size, you might want to try something on the order 10ms (480 samples at 48kHz).

And also to @Wookiee

I tried adjusting the BounceBufSizeMsec as you instructed, both to 10 and 20, but it didn't help so I put it back on 0 which was there by default for me.

Update #2

I have 3 FX plugins on the track in question. 1. Simplon (enabled), 2. Pro-Q 3 (disabled) and 3. Ozone Pro Imager (enabled).

What I discovered is that:

• if I disable Simplon, with Pro-Q 3 still being disabled but Ozone Pro Imager enabled, the corruption does not happen.
• If I let Simplon be enabled, Pro-Q 3 disabled OR enabled and Ozone Pro Imager disabled, the corruption does not happen.
• the corruption occurs if both Fabfilter Simplon and Ozone Pro Imager is both enabled. Fabfilter Pro-Q 3 doesn't matter whether it is enabled or disabled.
• the corruption occurs also if Simplon is disabled, but Pro Q 3 and Ozone Pro Imager is enabled.
• the corruption does NOT occur if Simplon and Pro Q 3 is enabled, but Ozone Pro Imager is disabled.

This is a real mess, and I guess @Wookiee is correct about the project being corrupted in much deeper ways, since there's not really a crystal clear logic to what causes this, since neither Simplon or Ozone Pro Imager does cause the problem by themselves only, but they might or might not cause the problem when combined with other plugins.

I've had projects seriously corrupted before, I mean REALLY seriously... total mess. The more you try to fix it, the worse it gets. It's NOT fixable, and the only thing you can do is to go back to earlier versions before the corruption even started.

Now I feel I'm on my way to this... the corruption use to start small, with small stuff, to get worse with time, until the entire project is so corrupted that trashing it is the only thing left to do... it's almost like a virus, spreading beyond control no matter what you do. I've written about this before in the following thread:

Edited November 6, 2023 by pulsewalk

[David Baay]

Does it reproduce if you delete everything but that track from a copy of the project? If so, you should save that stripped down project to  a new location, zip it up and send it to the Bakers.

[Wookiee]

@pulsewalk is this a pure audio project or is there some VST/MIDI as well. 

I would be tempted to create a new project import the audio a track at a time.

You can put any MIDI in the Media Browser as clips to bring back into the new project. 

Just a thought. 

[pulsewalk]

4 hours ago, David Baay said:

Does it reproduce if you delete everything but that track from a copy of the project? If so, you should save that stripped down project to  a new location, zip it up and send it to the Bakers.

I can try, but I don't think it does. I actually accidentally just discovered, that in another version in the project, the audio engine is stopped at the same point, but that corruption cannot be reproduced on that same track. Yeah, Ozone Pro Imager was actually missing on that very track in that version, but I added it and made a freeze and the corruption still didn't happen. Even though the corruption is actually there some where even in that earlier project. But it's on another track I guess.

It's moving around. ... I guess the whole project is corrupted. I hear clicks and pops (without audio engine being stopped all the time) here and there in the project. It's a real mess.

It gives me so much work I will maybe not even be able to finish it there. Will probably have to bounce everything very carefully, and just move to another DAW to finish. This is not the first time my projects are corrupted this way. I'm using the latest version of Cakewalk by the way.

[pulsewalk]

4 hours ago, Wookiee said:

@pulsewalk is this a pure audio project or is there some VST/MIDI as well. 

I would be tempted to create a new project import the audio a track at a time.

You can put any MIDI in the Media Browser as clips to bring back into the new project. 

Just a thought. 

It's a VSTi / audio project. But most of the audio comes from frozen VSTi tracks actually.

It's not so easy to import the tracks in another project, because most tracks contains some degree of automation, even the frozen ones that are automated AFTER they've been frozen. That means they cannot be frozen again with the added automation... Of course, one can unfreeze and redo the freeze with the new automation, but I have no idea what FX VST's are new in the rack of each frozen track and what is old. ..so that means I can't be 100% sure what FX was on or off when it was first frozen etc. That would need to be tested for each track with comparisons.... between the old and new freeze and so on... I can't do this for 130+ tracks...

Maybe if I had like 10 tracks, but that's not the case.

Edited November 7, 2023 by pulsewalk

[paulo]

May or may not be related, but I've noticed that freezing synths sometimes results in the same kind of thing. I freeze the synths for the obvious reason but do not apply any fx to the freeze so that they can still be tweaked afterward if necessary. Therefore, the audio clip should just be the synth output only, so to my way of thinking any "spike" that is potentially being caused by a plug in should not exist in the waveform and also at this stage of any given project it is very rare that there would even be any fx outside of the Pro channel, so to me that seems to rule out that it's some kind of plug-in issue.  Fortunately, the solution is always easy, unfreeze and then refreeze without changing anything at all and it's not there any more, or on some occasions it has moved to a different part of the track. (!)  So rinse and repeat and eventually all will be good.

I've also seen it happen when dragging an audio clip into the track view via browser. Delete the track and do it again and its gone. I have no idea how computers work and what they are doing behind the scenes at any given time, but there is nothing when I see this problem occur that would suggest that a third party plug in is to blame.

[pulsewalk]

UPDATE:

Just discovered that this type of audio engine failure, where the whole audio engine is killed after a "click/pop" and won't come back up until the buffers are "reset" in the audio driver + Panic button in the DAW, will happen if the automation goes straight up (opposite to a gradual increase to at least some degree).

Last time this happened was with Ozone 11 Stabilizer "Main Amount" controller. Every time I set the automation to go straight up (increase in value at the same instant), it will kill the audio engine in an instant with a click/pop, when playing through that part. Then it is dead. Must go to the audio driver, reset the buffer size (I have it on 1024 currently so I just set it to 48 and then back again to 1024), then click the Panic button in Cakewalk, and then I'm good to go.

If I make the automation increase a bit gradually, this does not happen.

I've encountered this with also other plugins, I think it's the same with Fabfilter Simplon but not a 100% sure. I'm just recently starting to understand the cause behind these clicks/pops, the audio engine going dead and so forth, so I've not reflected over what plugin and automation that does what. I'll be more observant in the future for what other plugins may be causing this.

I wonder if this is a problem/bug in the plug-ins or in Cakewalk?

Edited November 13, 2023 by pulsewalk

[pulsewalk]

UPDATE 2:

This might be a bug in Cakewalk actually. I just discovered, when zooming in really close... I mean, really, really deep down, that the automation was even "overlapping" in a place when this problem (described in the post above) just happened again.

So, the automation does NOT suppose to overlap. If you have an anchor, or "node", it should not "slide in under AND BEYOND the next one", it's a "big no no" since that would mean that two different values are being sent to the same controller to the plug-in, at the same time! That is not supposed to happen, even for a millisecond, I guess? It should not be possible to slide an automation point/anchor/node "beyond" the next one, so the automation path is creating a Z or an invert/flipped Z if you know that I mean.

Therefore, I guess that this actually might be a bug in Cakewalk, that Cakewalk let this happen in the first place. Whether this is the reason for the above described problem, or not, can best be answered by the bakers. However, correcting the "wrong" automation path actually DOES solve the problem.

@msmcleod could maybe shed some light on this?

 

EDIT: Here's a picture of how it looks. In another instant, the automation path formed an invert Z instead. This time, the anchors/nodes are not connected. Weird, since it should be the very same place, and same automation as before, though this is opened up again from an auto-save. Never mind, here it comes:

Edited November 13, 2023 by pulsewalk

[pulsewalk]

Just happened again. This time it can be seen it looks like an inverted Z. This is of course very zoomed in as you can see on the waveform above.

And of course, as I played through that point, it clicked/popped and the audio engine died. Will have to restart it as described earlier. There's no more audio playing before the audio driver is "reset", no matter if I use the panic button, it doesn't help.

 

Edited November 14, 2023 by pulsewalk

[Bristol_Jonesey]

Which parameter(s) are these envelopes controlling? This might be relevant to the bakers

[msmcleod]

@pulsewalk - yes, this looks like an envelope bug.  We've seen this from time to time, but unfortunately it's almost impossible to reproduce.

If you can get an envelope in a project in the state before this happens, with a reliable recipe for editing it to get it into that state afterwards, then please let us know.

The only thing you can do is edit the envelope to put it back to a sensible state.

[azslow3]

@pulsewalk Give them a project with the problem...

Background. Automations in Cakewalk are saved as segments, using Musical time (ticks). Each segment has "start" and "duration", specified in Ticks. If "start"+"duration" is not equal to the "start" of the next segment, it can look like your screenshot.

How (and if) that can happened only Cakewalk knows. Even if it is aligned in ticks, it can be they calculate resulted sample  the way the result is no longer aligned.

Note that default segment type is "linear". But there are other types, including "jump" (in this case there will be no "previous value" point visible).

VST standard is fuzzy how automation segments should be transmitted to plug-ins. At the very same place in the documentation they claim there should be a linear segment for the whole block, then giving an example with single not block border aligned points. Then mentioning "jumps" should be specified with 2 points with the same time (sample). Finally technically it is possible to specify several points for a block, not in time order... And so, what Cakewalk does and how that is interpreted by particular plug-in is almost up to them 🤪

From the "user" perspective, check the following:

• do you have tempo changes in the project? If yes, are "Z" appears in such changes (only) or also at constant tempo?
• do you have "unusual" settings in Project/Clock? (not audio Sync / TPQ != 960)
• how you create your automations? (controller, moving knob/slider by mouse, editing points)