According to a post from a developer, this bug isn’t new in C12, so it’s been present for a long time I guess. A lot of people are, and have always been, as long as I can remember, complaining about performance issues even with an “empty project”. It’s this bug right there. So the devs were aware but never ever talked about it until November 2022. Better leave users struggle ugh?
I remember when C12 was released, an enormous amount of people complained about performance issues, and the sentence that came up most frequently was “even with an empty project” when they were trying to figure out where the issue could originate from.
Not only that, but it was also affecting clean projects that didn’t have the bug initially (projects created in C11 or earlier), and I am very sure it was the same bug. On some systems any project you would open would recover the bug. Now they fixed this, but it still remains when you create a new project right after launching Cubase. So yes, once you “fix” it and save, it will never come back on this project.
What @auggybendoggy3 says about replacing the default cpr file is a bit intriguing, because as I said earlier, when we open a project that doesn’t have the bug, any subsequent new project you create as long as you don’t close Cubase won’t have the bug either, and without fixing it in audio connections, we are able to save the project, close Cubase, and open this same project, and the bug will not be there. This would mean the issues comes from the Cubase.exe code and not from the project file.
Sorry for the rather long post but it’s in case a developer sees this. 