Audio sync drift on ~50% of VHS captures (AG-1980 + Sony GVD-800 + QuickTim

[CaliGator]

I’ve been reading a lot of older threads and guides, but I’m seeing conflicting advice. I know this topic has been discussed before, so apologies for the repeat — I’m just hoping to get a straight answer from people with real-world experience, especially for a Mac-based workflow.

Workflow
• VCR: Panasonic AG-1980 (line TBC ON)
• S-Video + RCA audio
• Sony GVD-800 as FireWire passthrough
• Mac mini 2013 (Mojave)
• QuickTime Player 7 DV capture (one file per tape)
• Must stay on Mac — WinDV not an option
• Drift exists in raw DV capture (before encoding)

Issue
• ~50% of tapes have gradual audio sync drift
• Starts in sync, off by end of tape
• Home-recorded VHS
• Drift amount varies
• No dropped frames reported
• Some tapes are perfect

What I’m trying to figure out

Is this typical VHS timing instability not fully corrected by the AG-1980 + Sony DV conversion?

Would adding one of these likely fix it?
• Panasonic ES10 / ES15 passthrough (VHS → ES10 → GVD-800 → Mac)
• Canopus ADVC instead of Sony
• Both together

Trying to build a reliable, set-and-forget capture chain.

[Alwyn]

Is this typical VHS timing instability

Play your tape directly to the TV and check the sync. That will help start to isolate the problem.

[pcspeak]

I Had Different Hardware!

I had a similar problem with audio drift, a long time ago.
I think I stopped using the S-Video connector and used the composite connections (yellow cable?)
Not sure if I got a better/cleaner video transfer, but the audio drift disappeared and the result was good enough for the videos I was converting.