Start Of Audio Muted in WL9.5.30 Renders with Certain Clip Plugin Combinations

I recently upgraded a system from Wavelab 9.0.30-64 to 9.5.30. Things seem to be mostly ok, but previous sessions (and new 9.5 sessions) with certain clip plugin combinations are now muting 50-250ms of the start of file in renders. The renders were and are always fine in 9.0.30-64. Of course it requires that there be audio at very start of file to really notice because 250ms is a relatively short time, but I get a lot of files from clients that have audio starting right from the left edge, so it has been audibly noticeable.

The original clip plugin chains were long, but I’ve narrowed it down to a couple combinations that are having this muting problem:

UAD plugin followed by Ozone (VST or VST3). mute.
UAD plugin followed by AOM Invisible Limiter G2 (VST3). mute.
UAD plugin followed by another UAD plugin.

(UAD followed by FabFilter Limiter is ok. no mute)

I’m using UAD Precision EQ, but it seems to happen with any UAD.
None of the plugins cause the problem on their own. Only in the combinations above.
I’m rendering Selected Clips or CD Tracks with CD markers on the edge of clips.
Problem doesn’t happen with the same plugins in combination in the Master Section.

I’m going back to WL 9.0.30 for the time being because I really don’t want to change anything else yet, but can anybody reproduce this (UAD followed by Ozone on clip, or UAD followed by Invisible Limiter G2 on clip, causing short mute at start of render files) ?

I can take a look tomorrow but in general, I’ve had some potentially related issues with plugins and plugin chains that would have a high latency or CPU load.

I think some things need to be looked at in this area but I have not had time to dig into it myself.

Sorry, one thing I just found. The UAD plugin should be unchecked in the clip plugin window to make the mute happen. The other plugin should be checked.

Sorry again. The FabFilter exhibits the same thing when the UAD is unchecked. So it’s:

UAD plugin (unchecked) followed by Ozone (VST or VST3) (checked). mute.
UAD plugin (unchecked) followed by AOM Invisible Limiter G2 (VST3) (checked). mute.
UAD plugin (unchecked) followed by another UAD plugin (checked). mute.
UAD plugin (unchecked) followed by FabFilter Pro L (checked). mute.

Sorry for being so disorganized.

And to add to the misery…

Any two exhibit the same thing if the first one is unchecked in 9.5.30.

Ozone (unchecked) followed by Ozone (checked). Mute
AOM (unchecked) followed by AOM (checked). Mute

But the mutes don’t happen in 9.0.30.

Sorry, I was really on the wrong track thinking it was a specific plugin. It does it with any plugins, as long as the first plugin is unchecked, and the second is checked.
One of the worst cases is Master Rig using the first Allen Morgan preset on both. That gives a 350-400 ms mute.

Confirmed. Exactly the same result. This must be a bug.

Thanks Stingray, I really appreciate it. PG, can this possibly be fixed in the next update?

Not in the audio montage, you say, but where in the montage? clip, track, output?

For UAD plugins, this option should be checked:
2018-07-25_07-53-44.png
If you deactivate it, is the problem still existing?..

Clip

Happens with any plugins.

One noticeable example (350 - 400 ms muted at start of render):

Slot 1 : Master Rig with Allen Morgan first factory preset (acoustic guitar I think). Slot unchecked. (so plugin inactive)
Slot 2 : Master Rig with Allen Morgan first factory preset (acoustic guitar I think). Slot checked. (so plugin active)

Doesn’t happen in Wavelab 9.0.30, so this system’s back to that version for the time being. Whenever it can be fixed, I only just upgraded this particular system.

Please answer my last question too, which might be the key…

You mean deactivate both slots? I’ll have to try it tomorrow.

No, I mean deactivating the dynamic switch which is specific to UAD. See my picture.

I still see/hear the bug here regardless of the status of the dynamic switch (tested with MasterRig as outlined above). A short segment is muted at the start of the rendered audio.

Do I read correctly: a UAD plugin must always been involved?

No. This occurs in a plugin chain without any UAD plugins. I can repro this both with MasterRig and Multiband compressor, for example. See Bob’s repro procedure for MasterRig six posts ago (above).

Thanks Stingray. Yes sorry PG I turned this thread into a mess until I found out it happens with any plugins on Clips. The length of the mute is different for different plugins, latency, processing I guess, but they all exhibit the mute to some degree, if the first plugin is deactivated and the second plugin activated.

I can reproduce, and I am currently trying to understand the problem.
You have a (kind of) workaround: before rendering,remove the plugin, rather than leaving it unchecked.

I found the problem, which will be fixed in next patch. See the workaround of my previous message in the mean time.

Thank you so much PG. That’s great.