Check the other thread on grips. I have a similar issue with a no name brand as well. I've now taken it off the camera and will be returning it.
I think it is safe to assume that the failure rate for these cheap units will be fairly high. Having said that, I am not dismissing third party grips completely. If there is a good quality one out there then I will look at it.
I don't subscribe to "buy Nikon or nothing", as it is clear that they aren't perfect either, and I find $350+ for a grip just a little hard to digest.