The Kronos and computer audio outputs will need to be captured/routed in some way, so both can be heard. There are quite a few different ways to do this, but here are a couple of suggestions. If you only want to use Sibleius for music notation and scoring and not for audio, ignore the next paragraph:
Connect the Kronos L and R Line Outs and the computer's L & R audio outs to a stereo mixer, or route the Kronos Line Outs into the Line Ins on the Computer, and use suitable mixer software. Use Sibelius' preview (Test?) feature to play Sibelius' internal sounds, and of coursethe Kronos' keyboard to verify it is all working.
Download the latest Korg MIDI driver from here:
https://www.korg.com/us/support/downloa ... /424/3541/
Do NOT connect the Kronos yet!! First install the driver software.
Connect one of the computer's USB-A (the oblong shaped) ports to the Kronos' USB-B (square shaped) port. Once the computer has recognised the Kronos is connected, go to the Sibelius MIDI control panel and select the Kronos as the MIDI device, both for input and output. I don't have Sibleius, so cannot help with the exact details. It should be possible with this setup to use the Kronos as a MIDI keyboard to enter notes, and also as a playback device, to play sounds using MIDI generated from the musical score loaded into Sibelius. If at all possible, try and use the same computer USB port each time the Kronos is connected.
This will hopefully get you started. I'm sure there will be further questions.
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