Hello, I'm sharing this information because after upgrading to mac sierra and logic x 10.3 I struggled to get my kb37’s midi notes to work. Thanks to the line 6 help support and running a series of tests i hope this information can be of assistance to anyone facing this problem.    Step 1.  Download 7.6.4 and 7.6.5 from here - http://fr.line6.com/software/?hardware=PODxt&name=Drivers&os=Mac+OS+X&submit=Show%3A uninstall line6 first and keep kb37 disconnected from computer. Uninstall is available at applications folder -> line6 -> drivers -> line 6 driver uninstaller   Step 2.    install 7.6.4 and when u get the page where it says customise (bottom left hand corner), make sure the following preferences are checked for the installation   (a) audio driver (b) midi driver (d) line6 twx framework   Step 3.    restart and make sure usb of kb37 is disconnected from computer   Step 4.    install 7.6.5 with following preferences checked © audio-midi   Step 5.    restart and make sure usb of kb37 is disconnected from computer   Step 6.    connect usb of kb37 to computer and it started working for me   Important note:    Now every time i start up the computer, i need to make sure kb37 is disconnected before i start it up for it to work. Some of my midi keys started working strangely with logic as well (some notes are playing cycle mode).    If you find a better fix than this pls let me know. This is the best workaround i’ve discovered if you are having the problem where Kb37 is not working with logic pro X 10.3 on mac sierra 10.12. I understand this is the el capitan thread but maybe a similar process might work.