This is a known bug in Sonar v1.02. If you are using SMPTE/MTC as a timecode source, pressing play will switch the source to Audio and sync with your gear (e.g. Adats) will not work. The solution is to record enable and mute an unused midi track and to press record instead of play. This will playback all other tracks, but keep it away from playback mode, thus circumventing the problem. If you are not using sync, this is not a problem.