You don't have an AC3 codec installed. Since almost every DVD has audio done in AC3 format, it's kind of an important thing to have.
So, you can either download and install a freeware AC3 decoder like AC3Filter http://ac3filter.sf.net or just download a better overall player like VLC Player http://www.videolan.org/vlc/
I have lost the audio from my DVD writer/player. When I try to play Commercial DVDs, in Windows Media Player or Nero Show Time, there is no sound. Although, .avi files and .wmv files stored on my hard drive play just fine. And the DVD/RW drive plays audio CDs.
There used to be a speaker icon in my system tray. I have removed it permanently, I have since flushed the Recycle Bin, could that be the problem? There is a RealTek Audio Manager icon in the system tray; its 4 master volume controls are all at 40%.The Control Panel/Sounds and Audio Properties /Hardware tab leads to the same Audio Manager dialogue window.
Please help me, this is day two. Just moved to XPsp2.
0OS Name Microsoft Windows XP Home Edition
Version 5.1.2600 Service Pack 2 Build 2600
OS Manufacturer Microsoft Corporation
System Manufacturer ASUSTek Computer INC.
System Model P5GZ-MX
System Type X86-based PC
Processor x86 Family 15 Model 6 Stepping 5 GenuineIntel ~3199 Mhz
Processor x86 Family 15 Model 6 Stepping 5 GenuineIntel ~3199 Mhz
BIOS Version/Date American Megatrends Inc. 0601, 11/30/2006
SMBIOS Version 2.3
Windows Directory C:\WINDOWS
System Directory C:\WINDOWS\system32
Boot Device \Device\HarddiskVolume1
Locale United States
Hardware Abstraction Layer Version = "5.1.2600.2180 (xpsp_sp2_rtm.040803-2158)"
Time Zone Central Daylight Time
Total Physical Memory 1,024.00 MB
Available Physical Memory 563.76 MB
Total Virtual Memory 2.00 GB
Available Virtual Memory 1.96 GB
Page File Space 2.39 GB
Page File C:\pagefile.sys

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