OSC 2 switches on automatically

Hello everybody!!!

So I have the following problem:
If I only use OSC1, after a certain time (about 10 seconds) OSC2 switches on automatically.
I only play on the keysboard and do nothing in VITAL!
I am despairing, because I don’t know where the error could come from.
Maybe someone would be nice enough to help me, or it is simply a bug in the program !?

Would be nice to hear from you!
best greetings from Mondsee

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