Audio drift with ATI TV Wonder 600 USB?

[dream_emulator]

Hi all!

This is my first time posting here, so apologies if I miss something or put this in the wrong place.

I've recently upgraded my VHS capture setup from barebones (standard VCR into ElGato) to something that is actually useful. (Please see "Capture Setup" below). I have been trying to capture through this setup, but I have noticed significant audio drift. This starts small, but by the end of an hour long capture, the audio is noticeably off (couple seconds behind).

Background
I retrofitted Windows 7 onto my HP EliteDesk 800 G3, which was a bit of a hassle, but seems to be running well now.
I have installed the recommended Windows 7 ATI TV Wonder 600 USB drivers that are available on this site.
I am sending both S-Video/Audio from the HS-U795 through the DVR-640H, and into my ATI TV Wonder 600 USB, which as far as I can tell is connected to a USB 2.0 port.
I am saving to a secondary internal SSD (OS not installed on it).
VirtualDub does not show frames being dropped.
Video is compressed with Huffyuv v2.1.1
Audio is not being compressed.
Audio Playback is disabled during capture.

Timing Settings:
[X] Drop frames when captured frames are too close together
[X] Insert null frames when captured frames are too far apart
Null frame burst limit: 10

Resync mode:
[X] Do not resync between audio and video streams

[X] Automatically disable resync when integrated audio/video capture is detected

Audio latency determination:
[X] Automatic - Number of audio blocks to use at start: 30

DirectShow Options:
[X] Disable timestamps for preview
[X] Force audio clock when audio playback is enabled


Things to note:
VirtualDub shows CPU usage fluctuating between 15%-50% (which seems strange to me, but maybe this is normal)
I am noticing jitter of -3ms at times, but I do not know if this is significant enough to cause a major delay.
I did try having audio bypass the DVR-640H entirely, but that resulted in worse drift.
I have experimented with multiple tapes, and drift is consistent across them.

I have attached some screenshots of my configuration as well as capture in progress.

Thank you in advance for any help or suggestions. I'm looking forward to getting involved here.


Capture Setup

Hardware
VCR: Mitsubishi HS-U795
Line TBC: Pioneer DVR-640H
Capture Device: ATI TV Wonder 600 USB
Capture Software: VirtualDub 1.9.11

HP EliteDesk 800 G3 SFF
OS: Win7 Home Premium
Ver: 6.1.7601 SP1 Build 7601
CPU: Intel i5-7500 @3.40GHz
RAM: 16GB DDR4
C Drive: NVMe (Internal) 1TB
E Drive: SSD (Internal) 512GB
BIOS: HP P-1 Ver. 02.50

[lordsmurf]

Welcome.

1. Pioneer DVD recorders don't really have TBCs of any consequence. Definitely not ES10/15 quality.
2. No frame TBC in your workflow, and frame TBCs prevent audio sync errors.

That said, those bottom two audio Timing Settings, "Disable timestamps" and "Force audio", should not both be selected. However, I don't this is the issue here.

I don't own/use (and sell) TBCs because I enjoy it. I didn't want to spend money on those either. But these are the tools needed for doing quality work, problem-free work. Too many people have this weird idea that TBCs are "status symbols", and are not needed. Wrong.