"Stop At Project End" Mutes Audio on Rewind

While troubleshooting the No MIDI Meters When Recording problem (which seems to be due to projects started in previous versions of Sonar), I started encountering a very repeatable case of losing audio output while playing soft synths and input monitored hardware synths. To make a long story short, I found that hitting Rewind would cut off the audio output, even though the audio engine indicator was still lit, and the audio track's meter was still registering output level. If I held a note or chord, I could alternately hit Spacebar and W, and the sound would come and go as though I were toggling Mute.

On a hunch, I unchecked Stop At Project End in Global Options, and sure enough, Rewind no longer kills audio.

I'm thinking this might explain the miscellaneous reports of mysterious lost audio output that have been popping up in various threads recently.

No, that's something else. In this case, the audio level is there "in the system" so to speak, but SONAR is not passing it to the interface - just like when you mute an audio track, except that you still see the level in the meter.