Finally we've a proper solution for scanning a velocity sensitive keyboard at fast speed (300 uS) with low CPU load (so that other tasks can be processed in parallel). -> http://svnmios.midibox.org/listing.php?repname=svn.mios32&path=%2Ftrunk%2Fapps%2Ftutorials%2F029_keyboard_velocity%2F I tested it on a defective Korg microKONTROL - the original firmware scanned the keyboard only at 500 uS, which means that the app has a higher accuracy than the commercial solution. :)