"is there any negative effect or loss in sound quality feeding 24/96 data to a 16-bit DAC (like the Havana)"
It depends on the resolution of the source files being served.
If they come from CDs, then I would expect not assuming everything is working properly because these are only 16 bit to start.
If they truly come from other higher (than 16 bit) resolution sources, then maybe assuming that the true resolution is in fact greater than 16 bits. If it is a 16 bit source that has been oversampled to a higher sampling frequency, for example, then probably not.
It depends on the resolution of the source files being served.
If they come from CDs, then I would expect not assuming everything is working properly because these are only 16 bit to start.
If they truly come from other higher (than 16 bit) resolution sources, then maybe assuming that the true resolution is in fact greater than 16 bits. If it is a 16 bit source that has been oversampled to a higher sampling frequency, for example, then probably not.