Acer aspire 8930g audio

hi there, my name is jane…

i hope that you could help me… i just got a new acer aspire 8930g. everything in the audio is fine except when im playing a bluray disc, coz i can hardly hear the character voices. the background sound audio is perfectly fine, its just the caharacter voices which is coming out on the front speakers which is the problem… but whenever im playing music or watching a video stream, the audio is perfect… i’ve tried and searched on how to adjust it but to no avail… can you help me out please… thanks