I’ve looked back years in the forum, and apart from a couple of answers from forum users (that worked for the poster), i have had an ongoing problem of notes that i played a few minutes before, just start randomly playing.
On my computer i have made sure that Cubase is the only program active, and the chord track goes to a midi track with no output (one of the solutions)
I am surprised how it haas not been answered with someone from Steinberg trying to help with the problem.
I have had enough with this problem, as it keeps reoccuring, so sadly making the decision to move on to another daw.
If the next upgrade somehow fixes the problem, (but it has happened to me over two computers on win 10 and 2 upgrades of cubase, so i am not holding my breath), I will happily come back--------maybe
I don’t think this will be fixed any time soon. Why? Because you don’t provide any details that would help to get to the bottom of your problem. Instead, you just say that there is some sort of paranormal stuff going on
My advice in case you want to leave us like that would be: Who you gonna call - Ghost Busters!
Back on a more serious note:
Maybe you have forgotten to press stop and there are some leftovers somewhere down the line? As we are talking about minutes I would rule out that this is a delay/reverb. Maybe a VST instrument hangs?