Problem concerning Linking Midi Devices NEED HELP D:

Hey there, I've just recently got my hands on an A300 Pro which I have wired up to FL Studios 9 in order to work on musical compisitions and the likes. I was tweaking about with the settings - linking the controller to various dials, cutoffs, etc within the interface, but now the keyboard section won't play! It recognizes something is there, but it doesn't respond with any sound and is concurrent regardless of reseting the program or opening up a new project. Can anyone help me out with this problem?

Turns out this is only happening when in the Upper mode. I can play normally in Lower, but I want to regain keyboard inputs for Upper, any details on it?
The Keyboard hasn't broken, all the other dials and buttons work. I'm running a Windows 7 x64 operating system, if this affects anything.

Thanks for reading!