This issue seems related to this:
thanks guys, i finally found a related link within the other links posted here and that FIXED it.... but seems to have broke my dazzle in the process...
But it could have been happening before and went unnoticed.
I found a few posts on the sister forum
Vistax64 that looked promising.
the other one (halo3...) is a broken link - it never loaded.
the other one post pointed to this drivers page:
Pinnacle - Dazzle* Hardware Installer for Studio 10
Note: The files contained in this package are hardware drivers only.
Beside the driver, a compatible version of Studio is required.
Click on the selected driver, according to your hardware and operating system and download it to your hard disk.
Then double click on the file to start the installation
*: This Vista 64bit driver was not tested with Studio 11 and previous.
Important Note: MovieBoard 500-PCI/700PCI has an issue on Windows 64 bit systems when the computer has 2GB or more system RAM.
In this case Studio will crash during capture.
For this reason other capture devices are recommended on most Windows 64 bit systems.
I'd suggest uninstalling the drivers you have, restart the box (might not be necessry, but...) and install the 32 bit versions of the device driver from the link above. Why the 32 bit - read the * on the driver site about Vista 64bit (yes Vista... same column as Win7 in the driver list)
See how the drivers behave using Media Center as Solarstarshines suggested. Test some other front end applications that can use the device (webcam?).
If all is well,
think about installing the appropriate Studio software (SW). If you do install Studio and the device acts oddly again, you know it's because of the Studio SW. If Studio SW causes the issue - uninstall it and use something else.
If Studio behaves, you might find some configuration tips here: The video author sounds young, but that doesn't mean anything. There might be something on the site that helps:
Best Dazzle Settings (Dazzle DVC 100) | HDPVR Quality | How To Save Money And Do It Yourself!
I had a Pinnacle card in an older machine, the Studio SW was a resource hog, so I took it off in favor of less resource intensive applications. Which ones?.... it was a very long time ago, I don't know if I just used native Windows applcations (Media Center didn't exist then) or if I found something to replace Studio.
Anyway, that's all I can offer. Good Luck.