Several Studio One users reported a problem when adding many different (unique 3rd party) VST plug-ins to a song. At some point, Studio One would no longer allow more plug-ins to be added. This led to some confusion and speculation we would like to address.
First of all: there is no plug-in limitation in Studio One per-se.
However, there is a limitation on the Windows platform of how many DLLs depending on the statically-linked C runtime library (https://en.wikipedia.org/wiki/Runtime_library) can be loaded into a process. It’s a problem that has always been there but for some reason hasn’t surfaced until recently. There is little documentation about the limitation and it varies depending on the Windows version and compiler version being used. According to Microsoft, this behavior is "by design".
This issue affects all host applications written in the C++ programming language, except those who allow loading plug-ins into separate processes (which isn’t always feasible for low-latency real-time audio applications). Depending on how many DLLs are used by the host application itself the number of additional 3rd party plug-ins that can be loaded varies. The problem is made worse by plug-in developers also using the static version of the C runtime library.
Studio One 3.3 has been built with Visual Studio 2015 and dynamically link to the new Universal C runtime library. This significantly increases the number of additionally loadable DLLs.
At Presonus we’re committed to provide our customers with world-class customer service and product quality. We will continue pushing the limits for performance and stability of our software, and at the same time team up with our 3rd party plug-in partners to come up with better overall solutions. We like to extend our gratitude to those users and beta testers who helped us in identifying this issue.