ive got a Dell Inspiron 6400 laptop that I need a microphone for a disco to work. Plugged a Sony F-v120 microphone into the 3.5mm jack, laptop detects audio device presence, click on OK but no sound out of speakers. Checked all settings for speakers for muted, all switched on. Used the microphone as a recording device from same jack input, recorded ok. Rang Dell, wanted £35 just to help me even though laptop only 3 months old. Any help appreciated as I'm no Bill Gates. Is their such a devise as a USB mike? would this cure my probs. Tried an exchange mike but still same prob...