SOLVED--electric piano no longer plays without Sonar open

I am something of a DAW noob, so I really appreciate your help here.

I have an electric piano hooked up directly to my computer's sound card with midi cables. When I installed Sonar, it still worked fine. When I figured out how to use the piano to trigger the instruments that come with Sonar and record midi, it worked fine. When I installed my EastWest samples and Play, I could trigger samples and the keyboard was still fine on its own. The problem seems to have happened when I created a project using the Play engine as a software instrument in a project.

Now, when my piano is on but Sonar is not, I can't make any sound come out of the piano by hitting the keys. If I use the demo mode sounds come out just fine, just nothing when I press the keys myself. If I have the specific project open--in which I inserted the Play Engine and mapped various sample instruments to specific midi channels--I can trigger the samples just fine and SOMETIMES also play notes out of the keyboard. I've tried putting all the samples back to omni and looking for anything I might have done weird in the inputs and sends, but I can't figure it out. Any direction someone could point me in would be GREATLY appreciated. If I seem to have left out any pertinent information, let me know and I'll tell you what I can.





TL;DR:


After setting up Play Engine in Sonar, my electric piano is silent when I press the keys, even when I do not have Sonar open. There doesn't seem to be anything physically wrong - is it possible there's a setting I've screwed it up with?

Thanks for your reply.

All of the the tracks are now set with midi echo "on", but the problem persists. I can hear my piano's native sounds when playing with Sonar open, but not when the project is closed. This did explain why I sometimes heard my piano with the project open and sometimes not, though - I think as I was trying to troubleshoot I inadvertently switched midi echo off for a few of the sample instruments.

In Preferences>MIDI>Playback and Recording, the "Always echo current MIDI track" box is checked and has been since before the problem. Is there some other place I should be finding something that overrides this? Could it have anything to do with MMC or MTC settings in Preferences>Project>MIDI? I haven't touched those settings since I don't understand them.

In case it matters: Sonar doesn't recognize that my piano exists. It only sees "midi input" from my sound card.