Im using a home built PC, 7th gen quad intel, 32 gigs ram running at 4.5 MHz using Windows 10 Studio One 4, there are no problems at all with plugins. When I upgraded to 4.1 nothing works. None of the plugins including the stock ones from PreSonus. All tracks play at the same time and mute/solo etc have no effect at all. Tried completely reloading everything, still a no go. So, since 4.0 works perfectly without any problems, I will continure to use that one and hope the next upgrade fixes this. If anyone has any idea why 4.1 doesn't work, would appreciate any input.