Audio out of sync and lag when playing high definition movies

[nobb]

Ok I am completely lost on this Ive tried almost everything and the best I could come with resulted in smooth video and audio, but the audio is out of sync. I'm using VLC player and Ive already played around with all the output modules, buffer settings, etc, and I still cannot seem to get smooth high definition playback on my system.

I think the issue might be related to the external USB Creative X-Fi card that I am using. Everything seems to be perfect, except when I use the optical spdif output to my 5.1 receiver then the audio will not be in sync. I can use the hotkeys in VLC to delay or speed up the audio, but that doesn't seem to do anything. My USB is operating at high speed mode and Ive got all the latest drivers installed.

Any suggestions would be great. My system specs below.

VLC player
Windows Vista Ultimate
Creative X-fi USB sound card
2gb ram
T2050 dual core 1.6ghz processor (it's a laptop)

 

[nickbits]

Your CPU might be too slow

 

[Atomic Playboy]

So you're passing the sound through a sound card and receiver, but you're just watching the image on the laptop screen? The processing being done to the sound by both the sound card and receiver could be introducing latency which would cause the sound to get out of sync with the video. An important point here: is the sound coming before the picture or after it? If the sound appears after the picture, it's likely that the additional chain of steps in sound processing is adding latency. If the sound is coming before the picture, then something else is amiss.

 

[nobb]

The sound is coming before the picture. Not that it makes a difference, but the video is hooked up to a bigscreen. I am almost certain it has something to do with the sound processing, but I dont know enough about this to narrow it down further. Strangely, Ive found out that KMPlayer works just fine though. Would really prefer to stick with VLC, but I guess I have no choice.

 

[PurdueRy]

Originally posted by: nobb
The sound is coming before the picture. Not that it makes a difference, but the video is hooked up to a bigscreen. I am almost certain it has something to do with the sound processing, but I dont know enough about this to narrow it down further. Strangely, Ive found out that KMPlayer works just fine though. Would really prefer to stick with VLC, but I guess I have no choice.

Have you tried waveout instead of default or directsound.

 

[nobb]

^Yup, tried all of the audio and video output modules.

 

[Atomic Playboy]

If the sound is coming first, it's the video processing being done by your monitor that is adding the latency. Most receivers have an option called "A/V Sync" or similar (Lip Sync, etc.). This will delay the audio by a specific amount of time based on the average latency exhibited by your monitor. Generally, these default to around 40 ms. If you are using a lot of post-processing options on your monitor (blur reduction, judder reduction, ee, dnr, etc.), you will notice that the monitor will take longer to process the image, and you will need to raise your "A/V Sync" to a higher delay to compensate or disable some post processing features in your monitor. Some monitors and TVs will have a setting called "game mode" which reduces many of the post-processing features to get as lag-free an image as possible, so if your receiver doesn't have an A/V Sync feature, you will need to see how much processing is being done by the monitor.

Although the fact that KMPlayer works suggests that the problem may lie in the VLC software and not in your hardware. Have you Googled or visited the VLC forums to see if this might be a common issue with the software? Does VLC have A/V Sync controls?