Recently I installed HybridReverb2 to experiment with convolution reverb. However, I found that it causes AM to crash on exit with any patch where it's instantiated. (This is on OS X 10.6.8, AM 2.2.3). Uninstalling it solved the problem. I'd read on the KVR forum that it's buggy, which seems to be the case:
http://www.kvraudio.com/forum/viewtopic.php?t=368935
Thanks, Ross, for helping me locate the gremlin in the machine.
dl
There seem to be multiple products on the market called HybridReverb. To be clear, we're talking about HybridReverb2 by Christian Borß (official page: http://www2.ika.rub.de/HybridReverb2/) It was released as part of the KVR developer challenge in 2009.
The plugin does appear to be buggy on Mac OS X at least. A while back I spent some time investigating this plugin. It crashes AudioMulch and many other hosts including Ableton Live, Reaper and Cubase. The crash occurs when you remove the plugin from your project, or close the app with the plugin still loaded.
I have been in touch with the author, who said he no longer has time to maintain it, but has said he'd be happy to collaborate if someone else wants to fix it. If anyone wants to contact him I have his current email address.
So yes, the solutions appear to be: steer clear of the plugin or put up with the crashing.