Do you have the output from the Aria player routed properly? The wavetable is a special case in Sonar because it shoots directly out to the system MIDI. The Player is a VST-instrument, which require audio outputs. You should have:
1) Midi track whose input is routed to Aria Player
2) An audio track (Sonar usually inserts a default "instrument" track) whose output is routed to the audio output of your soundcard.
To isolate it to SONAR or Aria do the Cakewalk VSTs, such as the TTS-1, pass sound?