On a recent trip to China I decided to purchase a 25RMB gamepad, because it seemed to have the most features for the price (about $3.66 USD). The driver that it installs is marked as coming from "Macro Vibration"; if the company ever existed there is no trace of it on the web. On the device itself the brand is Dilong. After some web searching, I found the product page...not much on it.
http://www.dilongsz.com/en/Products_detail.asp?ID=325
Anyway, I installed the driver and connected the device, and everything works. In Need for Speed (Most Wanted as well as Undercover), it is detected, and I can configure it, and other features, such as vibration, work too. But every couple of minutes, the controller borks and starts skewing the car to the left. If this was constant, I'd just calibrate it. But it doesn't happen constantly. In NFSUC, I'd open the Main Menu, and Alt+Tab out of the program and switch back. The controller works fine for about 5-10 minutes, and then the problem resumes again. The skewing to the left is all the way; i.e. turning the axis all the way to the right made the car drive (barely) straight. Can anyone help me with this issue?

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