Thank you!  :)

  When BitPerfect (or any other player, AFAIK) reports that it can recognize a DAC's capabilities, what it is really doing is polling the USB (or FireWire, or HDMI) format streams which the DAC announces during its connection handshake.  If the DAC announces a stream format that it doesn't...

Nope.  It's ...  defaults delete com.codetectonics.BitPerfect "BitPerfect_DSDDeviceCapabilities"   ... and it's case sensitive.

  Actually, we are very interested in providing EQ as a future enhancement.  We are looking at various ways of incorporating generic DSP into our audio engine that can be implemented without sacrificing audio quality to an unacceptable degree.  If we can do that, EQ becomes an attractive...