Video Transfer hardware - no video signal

I'm looking for some help on troubleshooting what appears to be a device or driver issue. The device is the Roxio VHS to DVD transfer cable, and the Roxio support people couldn't help. I know the cable and it's software work, they work on a borrowed Windows 7 machine. So it's got to be a Windows or laptop issue.

I purchased this product, which is a hardware cable that attaches to the Audio Video composite outputs on a VHS tape machine or other player, and to a USB port on the laptop. Then you play the tape machine, and it shows in a window in the Roxio software while it records the AV data into an MP4 file. Only no matter what I do, I get "No Video Signal detected" error from the Roxio software. It just can't see the video data.

1. I did the install from CD. It installed clean. Then I plugged in the device, and PnP installed the device drivers, and they installed ok. But I got the "No Video Signal Detected" error.

2. I uninstalled and reinstalled, 4 times now. Once, I used Revo uninstaller and did a clean install, the other times I either uninstalled it from control panel and reinstalled, or just installed over the existing installation. Still the same error.

3. I deleted the device drivers, unplugged the device, rebooted, and replugged the device. It found the disk with the device drivers and the device drivers installed ok and were reporting working in Device Manager. I did this about 5 times overall.

4. We tried disabling some other drivers in Device Manager, like printers. Didn't seem to hep.

Now in the middle of all this, i installed this on a very similar laptop (same age HP laptop as mine, sightly different model, same OS). It installed fine, and it worked!!

So now I'm stuck. Best Buy will not take software back, and really it's not the device. But I'm stuck with a non-working device. Does anyone have an idea what might be going on, and how to troubleshoot this? I figure there is probably a good general method for proceeding. The drivers appear to set up ok, and software ok, just no signal on one machine, but works fine on another.

Steve

Yes, I tried all three USB ports. No different. And the laptops are not identical, they are the same brand and similar age and similar model. But both are 3 years old, so over time with different uses and software installed they are likely different in myriad ways.

I know no one is likely to be familiar with this device. But does someone have a method for tracking down whatever conflict or issue this is? It's unlikely to be hardware I think, since the USB ports have functioned well so far. Maybe a driver conflict (or not, there are no non-functioning drivers as far as I can tell, and these drivers install fine).

The simplest method may be to run Speccy and/or CPU-Z on each computer and compare. I was running an old Cyberlink program and was forced to update when using 7. At the time could only get their newest and greatest which required a cpu with multi threading. Mine does not and there was no mention in the program specs. My money was returned without question however, and I was forced to go with a different program.
Art.

Thanks. We pretty well know it's not hardware, so speccy and CPU-Z are not going to be much help I'm afraid. The hardware is all working and nearly identical (a bit more HD space on one, a bit more RAM on another). It's got to be some sort of OS or port or some type of setting I think, or a conflict of some sort.