OS X :: Use Keyboard Volume Button And External Audio Interface?

I have an Audiobox USB audiointerface with KRKROKIT5 speakers and must turn up or down the volume on the interface. the Keyboard button wont work.

But my father uses Bose speakers but can do both! However, he does not use an audio interface.

Can I get my imac to do both? And if so, is this a good idea with such good speakers? Is the keyboard just turning it up digitally?

I only ask because it can be annoying reaching up over the speaker to turn the nob instead of just hitting a button on the keyboard.