The adapter chord has 2 MIDI connections on one side (midi in and out?) and a USB connection on the other side. I can hear the Korg O.K. with earphones. Is that O.K? If not, I'm hosed . . . I don't know of any sound input on my laptop.
What is the brand name and model number of this "adapter cable" you are using? You have to know which plug is in and which is out... find out and label them if necessary.
Where are the headphones connected for you to hear it "ok"? To the computer or to the Korg headphone jack or somewhere else?
Knowing the cable name and model will help us to figure out the problem. In other forums, we've seen folks come in with those $20 midi cables and quite often, those things are not worth the time or money and folks have a hard time getting them set up properly...and other times, they work fine.
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