Can't Burn DVDs in Boot Camp'd Windows 7

So I'm running Windows 7 on my Mid-2009 MBP (OSX 10.6) through Boot Camp, and for some reason it won't burn DVDs. I've tried doing it through Windows Explorer, the Windows Disc Image Burner, and a third-party program called ImgBurn. None of them will write to the disc at all. However, I can still play DVDs. I've tried updating the driver (says it's up to date), and uninstalling and reinstalling the driver. No change. Any idea what I can try to fix this?