The activity meter on the instrument track shows level when the MIDI keyboard is engaged, but there is no audible sound. When recording, the input data translates into the track, but does not produce audio while recording or during playback. Under Studio One/Options/External Devices/Edit, 'PreSonus PS-49' is selected in the 'receive from' bar, and 'none' for the 'send to' bar.
The PS-49 manual says "No driver installation is required for your PS49 USB MIDI Keyboard... your PS49 is preconfigured for use in Studio One so no setup is required to use it as a controller." This leads me to believe that I can simply open Studio One, create a new song, and the MIDI will be ready to use right away. This is not the case.
I am having a similar issue with my mic that may be related. My AudioBox USB interface seems to be functioning properly. The mic that is hooked up to it is picking up and producing sound, heard in my headphones and shown on the activity meter. However, when I record with the mic, it does not render in the application. The take is empty as if I recorded with my mic off, and obviously no sound comes through in playback.
(For what it's worth, I've looked at countless articles, videos, and forum discussions relating to standard MIDI trouble. None have proven entirely helpful.)
If these issues aren't linked, I'd like to start with finding a solution to the MIDI problem.
UPDATE: I fixed the problem. I took a break from troubleshooting to download some soundfonts and get some food, and somehow in that process the problem fixed itself. I'm not quite sure why it's suddenly working but I think it has something to do with my lunch.