FabFilter User Forum

Fabfilter Pro C2 external sidechain bug in Pro Tools?

I noticed in Pro Tools when you use external side chain in Pro C2, if you collapse the sidechain breakout box, sidechain stops working, which seems odd. In Pro C3, if you collapse the breakout box, sidechain continues to work, which id expect.

Quick video showing what i mean.

drive.google.com/file/d/1s9bjbXbP3i-3hZAOXb2xZGuPvyHsY1CN/view?usp=sharing

Matt Leschuck — Feb 19, 2026

Hi Matt,

This is not a bug in Pro-C 2, it always worked this way. We changed this behaviour in Pro-C 3.

Maarten (FabFilter) — Feb 19, 2026

Thanks for the confirmation Maarten, I have Pro-C 2 and that one threw me off a bit.

Matt — Feb 19, 2026

Reply to this topic Go to the forum topic list