Hi there. If you are using a Roland interface, make sure you use the Roland drivers which should be asio compliant. Roland kind of invented midi. This means they adhere quite strictly to the midi specification. As for external devices - which ones? I have two Roland drum modules and both work fine, with little to no set up. As for a Roland keyboard, again, mine was added with little fan fare. My keyboard is effectively two devices - one being the main keyboard, the second being fader and rotary controls with a set of drum pads. On my Roland A-800 Pro both devices are mapped giving me total control over Presence, Mai Tai, etc. Studio One has a very powerful "set once" midi mapping for control surfaces with both global AND instrument focused settings. By which I mean, you can map the keyboard functions in one song and then everytime you open a track and use that keyboard, your mapping is remembered.
