Sound Problems!!!!

I Noticed this only today & its a very strange problem.My speech doesnt seem to be working.The player names are not bein announced by the commentators or by the arena announcer and even the team introduction isnt working.I checked the volume and the dbf files for the id7 fields but all seem to be ok.Any help would be greatly appreciated.
Thanks

P.S-All other ingame sounds work.

i've been having the same problem 4 a while now, i've checked my speaker 4 any problems and can't find any. if any one knows how to fix this problem, plz post it