I'm at work, so don't have the MPC on hand, but I think I found the answer in Addendum 1.20.
http://www.akaipro.co.jp/jp/datalib/dow ... kad120.zip
In the Main Screen, scroll down to the Trk Block and then move the cursor to the
"Mute" field and then press the "Window" key. You should see the Track Mute Event
screen. Go to "Use Track Mute Events" and change it to "On".
I believe that's what you were asking for , correct?