No rear sound

chr1st1an · 02-23-2006, 08:35 PM

Hi, I have a Biostar motherboard with the realtek ac97 5.1 audio card on board. When I do the speaker test my 5.1 system works fine. But when I play a movie with 5.1 ac3 I only hear front and subwoofer sound. In some configurations of WinDVD or Windows media player I get sound from rear, but it is an upmix from the other outputs, not a real surround.
I downloaded a test movie which tests all the speakers. I played it with WinDVD and i get only sound from front, center and sub. BUT, I tried to demux sound stream with virtual dub mod and save it to an AC3 file and then play that file with WinDVD and.....it work! I hear the correct sound from all speakers (except from sub, dont know why)....
So, why in the movie dont hear nothing from rear but the audio stream alone works fine?
I think is a software problem, but can't find the solution.

thanks
Christian

02-24-2006, 04:30 AM

Hi Christian. Welcome to the forums,

is an NVIDA chipset? If so and you are using the nVIDA version of the realtek drivers you will likely need to switch to the actual realtek AC97 drivers to get proper 5.1 output from movies and be using a full retail version of WinDVD, or PowerDvD, or nDvD (nVIDA). It also could be in your speaker setup config (EG if you only have 3 jacks you will need to set speakers for line-crossover (but it looks like you probably already know that).

02-23-2006, 08:35 PM	#1 (permalink)
chr1st1an Registered User Join Date: Feb 2006 Posts: 1 OS: XP	No rear sound Hi, I have a Biostar motherboard with the realtek ac97 5.1 audio card on board. When I do the speaker test my 5.1 system works fine. But when I play a movie with 5.1 ac3 I only hear front and subwoofer sound. In some configurations of WinDVD or Windows media player I get sound from rear, but it is an upmix from the other outputs, not a real surround. I downloaded a test movie which tests all the speakers. I played it with WinDVD and i get only sound from front, center and sub. BUT, I tried to demux sound stream with virtual dub mod and save it to an AC3 file and then play that file with WinDVD and.....it work! I hear the correct sound from all speakers (except from sub, dont know why).... So, why in the movie dont hear nothing from rear but the audio stream alone works fine? I think is a software problem, but can't find the solution. thanks Christian

02-24-2006, 04:30 AM	#2 (permalink)
T_Rex Guest Posts: n/a OS:	Hi Christian. Welcome to the forums, is an NVIDA chipset? If so and you are using the nVIDA version of the realtek drivers you will likely need to switch to the actual realtek AC97 drivers to get proper 5.1 output from movies and be using a full retail version of WinDVD, or PowerDvD, or nDvD (nVIDA). It also could be in your speaker setup config (EG if you only have 3 jacks you will need to set speakers for line-crossover (but it looks like you probably already know that).