I got recently released 7" Huawei Mediapad, also known as T-Mobile Springboard.
I have the same issue, as described in some posts above: couldn't connect tablet with camera (500D, 550D) (camera: "BUSY" on screen message for a couple of seconds, and then works in its normal mode; app: "no compatible device....". I have already tried different firmwares such as Honeycomb, Honeycomb rooted, ICS beta not rooted - the result is the same. I have also tried to use additional power supply (Y-cable) - no result. At the same time USB sticks, mouses, keyboards work perfectly. Has anyone know how to solve the problem, or maybe someone have had no problem with connection of the same device?