A couple months ago their was white smoke coming from the vents - I had no idea what it was and after 2 days it never happend again... well last night i was checking out my fuse box and I think i discoverd the source of the mysterious white smoke.. that i believe is the radio fuse - (my radio/cd is working fine though) check it out and PLEASE give my your advice on what the hell happened - and I'm wondering what are those wires connected to those fuses and is there a relay missing up above their and what relays are those exactly?? thanks guys for your help!
http://i14.photobucket.com/albums/a333/joeylea/fusebox2.jpg

http://i14.photobucket.com/albums/a333/joeylea/fusebox.jpg
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http://i14.photobucket.com/albums/a333/joeylea/94pathy.jpg
My 94 XE-V6 Pathfinder

sounds like there is a short or a big current draw on your stereo, the fuse box is melted and the wires that are behind the fuse terminals could have got welded together. are you using the right rated fuse in it?