Hello everyone,
I'm having the same issue. Currently I'm using studio one 5, which it's great! but I have the same problem. It had never happened to me before. Now I'm having a P155 yamaha which I use as a midi controller. It worked fine, but just recently when I record I would have all the notes played wrongly. However, when I play I can hear that everything is perfect. The Midi playback is the problem. I also checked the Midi controler as andrrippstein suggested and I can see that when I press one key more notes are being sent. so, what can I do? Presonus please help me. I don't want to change my DAW ='(