rowan17:

are u sure that you are using an original keystation 49?
because if u are using a mk2 its possible that the oms driver simply does not work because
companies stopped supporting oms + macos9 around 2004
im not exactly sure when the mkII revision model came out (Which was branded M-audio instead of 'midiman') but i think its probably in 2005 or later and they probably gave zero concern about macos9