i had some freak happenings such as these
i worked out as audio I/O "sound card" issues
it was in the serial numbers of 400"s
and along with some other issues
the unit went back within the one year warranty period
and was replaced with a unit in the 1400"s serial number
that works perfectly every-time
other than the one outstanding issue (on all units)
http://www.korgforums.com/forum/phpBB2/ ... highlight=
and other "mistakes" in design (my opinion)
such as the "digital mixer" pre amp output "hiss" issue
and the none assignable cue channel (on a sound card?)
all of which it seems will not be dealt with
.................sorry got off topic,
i would sent it back with your particular description
are you talking strait up midi control, digital path,
or are you using an outside analogue source?
either way........i think its all digital at some point
mine was doing stuff with nothing plugged into it.......
i also mac