audio sync issues - why

[rh71]

Using an ATI TV Wonder USB with various software like Windows Media Encoder, VirtualDub/Mod to do the encode from VHS tape (connected via Composite cable/ (direct audio into my SB Live sound card)... even tried lower bitrates... I'm using the MP3 audio codec. It loses sync after a few minutes of playback.

My PC is a AMD (2.08GHz) with 1GB PC3200 RAM ... I don't think it's a hardware issue, right ?

What's causing these sync issues ? Is it just a dated capture card that doesn't perform well ? I'm thinking it's more a software thing because the audio comes in (line-in) just fine... the capture card should be handling video-only...

[pfh]

Probebly the card. AFAIK that card, decent tv tuner, but for capture it has no hardware encoding so your cpu is doing all the work.

[wwjd]

To expand a bit on what pfh said;

Since your capture card does not do the analog to digital encoding using its own chip set, it uses your computer's CPU. Analog to digital conversion is very CPU intensive. Hence if anything is running on your computer or starts to run during the capture process you will more than likely have video frames dropped (lost, not recorded). These lost frames will result in jerky video and audio sync issues.

[justinluck]

Is your processor an XP, Sempron, or A64? I've noticed that the A64s don't suffer from audio/sync issues as much as XPs.

[Stormin Norman]

Try and segment your captures, that might help. Say about 1-2 gig segments. Also instead of compessing your audio while capping, use uncompressed pcm instead, then compress after. Thats if WME lets you segment.