A:
I use mine for recording interviews so I don't have experience using it for instruments. However, there are 2 ways in which I would go around this problem. First, you could just play your organ while the recorder is recording and move that file into your computer (this should work just fine, but I would suggest testing the input levels to make sure that it sounds right). Alternatively, there is an aux port labeled "line in" for using your own microphone. If you have another microphone that you use specifically for music recording you could connect it there and it would work perfectly. Like I said before, I haven't used it for recording music so I really don't know how it would sound, but recordings of interviews, people talking, and even recordings of youtube videos sound perfectly clear.
Hope this helps.