That error is telling you FL can't find your primary audio driver. Whatever soundcard your computer uses is not on the same page as FL. Right click My Computer, hit the Hardware tab and click on Device Manager. If there is an 'unknown device' pertaining to audio in any way (You should get rid of all these anyways) right click, properties, and use the net to update the driver. If you have the drivers disc for your motherboard/sound card/dell then insert that. After you have cleared the unknown deviced go to FL>Options>Audio Options and at the top select the output device you wish to use. If you have no idea then guess, there aren't many options.
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