I´ve installed the Schoeps Double M/S Plugin and it works great, until it puts out noise and crashes Reaper eventually.
It seems to be connected with Repeat, after it plays back the time selection th e first time like it should, when looping it puts out zero sound or noise. A few seconds later Reaper crashes. VST, VST3 or AU, same.
I can´t say if it´s the same in other audio programs, because Repaer is the only one I have that can handle multi channel plugins.
OS X El Capitan, latest Reaper version 5.76/64
The Schoeps plugin is also the latest version, 2012 as seen here:
http://schoeps.de/en/products/categories/dms-tool
What to do? I will send a bug report to Schoeps as well.
Update:
Schoeps support says, this version of the plugin is not supported anymore.
They are working on a new version.
Good news!