[unsane]

i had this problem with the STOCK sprint rom....I believe it has to do with WMP....I did some tweaks that removed sprints links to the music store and that also took away my ability to have audio out...I am pretty sure it took away a driver because I didnt even get the headphones symbol on the taskbar when I plugged into the 3.5 jack.....I unlocked with hspl and burned Mighty Rom on the device and now is all good again.....I will say though that everything I tried before that to restore audio out on the stock sprint rom failed, so you may want to flash or reflash either Mighty rom or the stock rom to see if that gets it working for you.....Ive heard this problem has been happenening quite a bit in this forum....good luck!

Check and see if it works in another player instead of windows media...and look for the icon on the task bar when you plug in....no icon = no worky