Ensure that the 5-pin midi cables connect; MIDI/IN ->MIDI/OUT and MIDI/OUT->MIDI/IN (a very overlooked issue) if Mac; try MIDIMonitor. http://www.snoize.com/MIDIMonitor/ (free download) Open "Sources" then "MIDI sources", the mio should be listed here. Ensure that the boxes for these are checked. The window below should display all incoming MIDI data coming from the mio. Windows; When connecting the mio into your PC via the USB for the first time, Windows should recognize the device with a message "Installing device driver software". Go to: "Contol Panel/Device Manager/Sound, video and game controllers" The mio should be displayed in this list, if Windows recognized the mio properly. Try downloading MIDI-OX for your PC (free download). http://www.midiox.com On the top tool bar (4th icon from the left) there is an icon: "Display Raw MIDI Input" this will display all MIDI data coming from the mio. When you engage your midi device through the mio you should see the corresponding data listed here in real time. Open the icon next to it "Main Output Monitor". Now click "view/Device Info", this will display the mio in the Monitor-Output window as " IN: 1) mio OUT: 2) mio" Clicking "Options/MIDI Devices", you should also see the mio listed here in MIDI Inputs and Outputs windows. Under, "View/port status" the mio should be listed here as well. TIP: (if you are using a Windows operating system, ensure that no other programs are running on your PC, except for the one you are trying to connect to) If all these steps check positive, this will ensure that mio is functioning properly and that the problem could reside within the settings of your operating system or software program.