when i switch synths from the edirol hypercanvas to the forte dxi plug in the piano notes don't play at all

somehow generating a midi track isn't working quite right. i created a seq file using a friend's mp3 of one of his songs and although the acw seemed to get the chords right adding a midi bass seems to have gone wrong

i have a file with just the strange bass on to upload - is there a channel problem? (my only guess so far!)