Song duration and lyrics not showing..

I had a big song collection in one of my pc's with vista os. i copied the library to another pc with XP sp2 in it. i use songbird in both of them. in vista everything worked perfectly lyrics, duration album art etc. after i copied the library at first everything was fine. lyrics showing, song duration perfect.. but a few days ago i reimported(i only deleted it from the songbird library, and imported again) the songs. but this time almost half of the songs didn't have any duration or lyrics. the duration comes after i play any song for like 15 secs. bt other tags and album art are fine. i reinstalled the xp bt nothing happens. i tried copying again from the previous pc. bt no use its still the same. plz help
btw i use Songbird 1.2.0, Build 1146