FabFilter User Forum
No gain reduction in vari-mu mode for C3
same for me on Mac silicon with the vst3 version in Reaper and Cubase (Tahoe 26.2)
Thomas Junold — Jan 24, 2026
Well misery loves company, sadly. I sent an email to FF about this as there's no real way to start a support ticket or to report a bug on their website. I also tried it in Steinberg Wavelab 10 which uses vst format - same thing.
Jack — Jan 24, 2026
There's a bug in C3. No gain reduction when using vari-mu mode. No matter how much I vary the threshold there's nothing happening. Oh I see gain reduction in the plugin's metering but with an external level after C3 it shows no gain reduction. If I switch to another mode I get gain reduction. Anybody else seeing this? There's at least a couple of people over in Gearspace that are seeing this issue. Running in ProTools 2021.6 which uses aax format on a Mac running OSX 10.13.6