FabFilter User Forum
I cannot load Pro-Q4 into the FX-Chain of Sonnox ListenHub.
After updating Fabfilter Pro-Q4 to v4.11, I cannot load Pro-Q4 into the FX-Chain of Sonnox ListenHub. It worked fine before, but it won't run after the update. When I first launch ListenHub, the Fabfilter folder and Pro-Q4 appear in the FX list, but when I try to load Pro-Q4, it doesn't run, and the Fabfilter entry itself immediately disappears from the plugin list.
Tchangnsun Ryu — Mar 26, 2026
Hi Tchangnsun,
I'm not very familiar with Listenhub. Does it have a way to rescan the plug-ins?
Restarting ListenHub rescans it.
In other words, if you restart ListenHub, the Fabfilter folder and the Pro-Q4 plugin reappear in the FX list. However, when I try to load Pro-Q4 into the ListenHub FX-Chain, there is no response and it disappears again.
ListenHub is essential for my audio monitoring system because it allows me to run AU plugins on system audio. However, I am very perplexed that my favorite Pro-Q4 can no longer be used in ListenHub after updating to version 4.11.
And there is another error I just discovered.
I tried to see if the updated Pro-Q4 would run on HostingAU, another tool that can run plugins on system audio.
According to the test results of HostingAU, only the mono version is displayed in the FX list and the stereo version is not displayed, so Pro-Q4 for stereo cannot be loaded into the FX-Chain.
Can you see if rolling back to 4.11 makes a difference?
cdn-b.fabfilter.com/downloads/ffproq410.dmg
Thank you for your answer.
I uninstalled and reinstalled ListenHub and Pro-Q4 both, and after that, I was able to run Pro-Q4 (4.11) in ListenHub. I have no idea what on earth caused the error before, but anyway, it is resolved now.