THANKS for your suggestion, it makes perfect sense, it's 5:30AM and I don't have time to follow up right now but will definitely do as you suggest, it's not going to hurt to try at worst and just might work at best, definitely worth a shot and I'll post back with the results, thanks again!
Hi. It is my understanding that a midi to usb cable is actually an interface meaning it contains standard midi drivers. If it drives your other keyboard then why did you need to download midi drivers from Korg? (was that a dumb question?) The Korg drivers and the external midi cable interface could be conflicting with each other so I would think one or the other has to go. it is worth considering that this is where the bottleneck resides so you could try unplugging the cable, set the Korg to factory condition (if it has that choice) delete the korg drivers, restart windows, and plug the cable back into the Korg and start afresh with the Korg "striaght out of the box" I had a similar problem with a printer that somehow was installed twice and windows just sat ther chanting eeny meeny miny mo. Not being a Korg owner i have no other thoughts to offer but as a reader, this is the one thing that sticks out, hopefully this a "too simple to realise" cause so good luck.