Weird issue with sidechaining and U-he plugins in Waveform 12

[elcalen]

So I was taking Waveform FREE (12.1.3, Linux version) out for a spin and enjoying working with it until I encountered a weird issue with sidechain compression. I noticed that if I had more than one compressor sidechained from the same source track (like a kick), the sidechain input stopped working. Resetting the audio engine would sometimes fix the issue, but not consistently. The issue also persisted after quitting and reloading.

I did a bunch of testing. What I discovered was that I could only replicate the issue if I had U-he plugins somewhere in the audio chain. Doesn't seem to matter which plugin (I tried Hive, Diva, Presswork), or whether it's VST2 or VST3. It doesn't need to be on the same track as the sidechain compressor, could be earlier in the chain if using a submix or send. I can have sidechain compressors on other parts of the edit that don't have U-he plugins anywhere in the chain and they appear to function without issue. But if I have two or more tracks with U-he stuff with sidechaining from the same source, it just won't work (except sometimes after resetting the audio engine).

I use U-he stuff a lot, they make some of the best synths that run natively on Linux, so this is kind of a dealbreaker issue for me...

[terrynoakes]

Not really an answer for your question, but have you tried wrapping the vst in a rack to see if the problem still persists?

[elcalen]

Not really an answer for your question, but have you tried wrapping the vst in a rack to see if the problem still persists?

Wrapping the U-he plugin in a rack doesn't appear to change anything.

[elcalen]

A couple additional clarifications: I've mostly been testing with Waveform's built-in Compressor as the sidechain target, but I've confirmed that the issues seem to happen with other sidechain plugins as well. The audio routing for the U-he plugins causing the issues appears to be set to named/stereo input and output, which I think should almost certainly be correct...

[elcalen]

It's been almost a year since I reported this. I decided on a whim to check out the state of Waveform now, since my PC's had some upgrades since the last time. But after a bit of testing it would appear that the issue I described above still remains.

To test, I made a few tracks with samples or synths. Initially everything seemed to work OK. At some point while trying to copy a compressor plugin to another track, the audio engine crashed. Dunno if that's relevant. After restarting, the sidechain signal on tracks with U-he plugins no longer worked right, even after subsequent restarts of the DAW... (Waveform Free 12.5.11, Linux)

[pough]

Confirmed. Sidechain goes wonky with u-he. I wonder what could possibly be happening to cause this?

[elcalen]

One curious thing I noticed is that while the sidechain signal obviously doesn't work correctly when this bug occurs, there is still some kind of signal being detected by the sidechain compressor, and it does change at times. It's like the signal's stuck at a random level, but the level it's at keeps getting reset when hitting play or when playback loops...

[dysjoint]

Not uhe related but I have had problems sidechaining multiple plugins to one track. Haven't delved into it, just figured a workaround (creating ghost 'trigger' tracks)

[pough]

Not uhe related but I have had problems sidechaining multiple plugins to one track.

Do you mean sidechaining multiple plugins FROM one track? As far as I know sidechain come from a track into a plugin.

[dysjoint]

Yeah, I wasn't very clear. Multiple plugins on different tracks with the sidechain on all of them set to a single source track (eg snare). Got weird stuff like the assignment/link appearing to break, or stop being active (or not save??) Never worked out if it was plugin related or Waveform related, and wasn't too worried as that specific problem is easy to workaround (duplicate the source track)

[elcalen]

In my testing I only used a single source track, I think. (As mentioned, it's been a year since my initial testing...) But the only obvious issue I encountered (so far) was specifically with the U-he plugins, like I've described. Tracks that didn't have U-he plugins continued to receive the sidechain signal fine, from the same source. So I don't *think* my issue is related to the number of plugins drawing from the source track.

Of course I can't say for certain that the issue is *only* with U-he plugins. But out of the plugins I had easy access to and tested with, they were the only ones that triggered the bug.

(In any case, in electronic dance music the most common use of external sidechain compression by far is sidechaining from a kick, and it is very commonly used on *lots* of synth tracks. Duplicating the source track every time would not be a viable workaround, imho...)

[dysjoint]

Using busses can reduce the numbers down.

[elcalen]

OK, so playing around a bit more, I did indeed find that if there is only *one* track using that sidechain source, it does seem to work normally. And looking back at my original post from last year, I did in fact say that pretty clearly, heh... BUT, like I said, I can't really work around that; I would frequently want to sidechain to multiple compressors from the same source...

[pough]

I did some testing and when building the same project in other DAWs (Reaper + FL Studio) multiple instances of u-he plugins don't have problems.

New wrinkle: using #Tcompressor as the sidechainy plugin works without any issues. I was using cytomic The Glue in previous tests. It would fail if there were two or more u-he plugins.

New new wrinkle: I replaced #Tcompressor with The Glue and now it's working fine even though there are three instances of Hive in the edit.

[elcalen]

I've been mostly using Waveform's stock compressor for testing, but whenever I've tested others, the results were the same. (I'm on Linux, though, and using the Free version, so I probably don't have access to many of the same plugins...)

I've found that sometimes for me it seems to just randomly work again, for example after reloading the project. But not reliably, and then when doing something that changes the routing set up, for example adding another plugin with the same sidechain source, it all goes wrong again.

(I'm primarily a REAPER user normally, and I regularly use U-he plugins there without issue.)

FYI, I wrote a post about this on the U-he forum as well.