FabFilter

I observe frequent buffer underruns when inserting Pro-G at the end of a medium mixer plugin chain.
The setup is low latency asio (128 samples buffer) on a systen that can handle it.

Observations

1) No improvement when activating the internal bypass mode (!)

2) No improvement when disabling look ahead

3) No underruns when replacing Pro-G vst3 by vst2 version

4) No underruns when replacing Pro-G instance by Pro-Q2 vst3

5) No underruns when replacing Pro-G instance by a heavy computation
plar reverb vst3

Especially 1) and 3) makes me think that the issue might be related
to buffer sizes and/or asynchronous processing workflow.

Are there major differences between Q2 and G on the vst3 level?

Setup details

Pro-G: 1.19 and 1.20 (latest) x64
Platform: Windows 10 x64
DAW: FL Studio 12.4.2 x64
Hardware: i7-7700-K, 32 GB RAM, SSD drives
Interface: Steinberg UR 44

Hi Ulrich,

This problem doesn't sound familiar to us. One thing that comes to mind is it might be something in FL Studio's VST3 support combined with plugin latency. You mentioned that you tried disabling lookahead, but are you using oversampling in Pro-G? If so, try turning that off as well to see if that helps.

Cheers,