External MIDI - does not work

http://www.linuxquestions.org – Hi, been trying this for hours now with no success. I am trying to hook up an external MIDI keyboard to Ubuntu (Studio) with no sucess. I can play MIDI files but not get the s/w to reguster any events from the MIDI keyboard. I have a soundblaster LIve! with front panel and am usng the MIDI in on this, with a ROland PC-300 kybd. Headphones work fine on the panel so I know this has been connected OK. The software (Rosegarden) 'sees' the keyboard as in input device but nothing happens when I play. Really grateful for any pointers to what I can try next? (HowTos)