Possible solutions:
1. Make the Apple TV adjust its own output volume. (Apparently impossible?!?)
2. Make the TV adjust its optical audio output volume. (Also apparently impossible?)
3. Get a new audio device either just upstream or just downstream of the DAC that does nothing except respond to a remote control to adjust the volume. (Do such devices exist at non-silly-audiophile prices? What are they called?)
Any suggestions? I figure there must be something out there!
/end