MIDI-notes stuck when channel settings are open

I’ve come over an annoying bug after upgrading to the latest Cubase Pro 8 version: When I use the virtual keyboard to play MIDI notes while the channel settings are open or if I open it while playing, the note sustains and is not released until I close the channel settings window and I hit the exact same note again. This happens every time with any instrument.
Anyone else experiencing the same thing?
I use a Mac OS X Yosemite 10.10.2.