Finale does not enter pitch from midi keyboard

[dressage]

i am a mac user--os 10.5.8--using finale 2008.
when i'm in speedy entry, finale does not enter the pitch which i play on my synth kybd into the finale staff. if i press down a key along with a number value for the rhythm, i get only a rest for that value, not a note with pitch. for example, if i press down an a-natural on my keyboard along with a 5, i get a quarter rest.
i have checked "use midi device for input" in the speedy entry menu.
(if i uncheck "use midi device for input" i get actual notes, but only on the line or space where the cursor happens to be, not the note i play on the kybd.)
i should add i am using an mbox because i have protools and the midi kybd is connected to it.
i would love some help with my problem.
thanks!