HELP! NO SOUND!

[poisonarms]

ok, just purchased my microkorg today after a year of debating whether or not to get one. got it running through some studio monitors. it worked for about 5 seconds then, all of a sudden, i get no sound. i am able to listen to demo songs and i get sound from my vocoder mic, but when i just try to play, i get nothing coming out. ive tried the things (to the best of my knowledge) in the troubleshooting section of the owner's manual. though, im new to this kind of thing so i may be doing something wrong. help?

thanks!