iTunes+MacBook+Built-in optical digital output

I have tried 24bit/96KHz SPDIF output out of MacBook's optical digital output with non-compressed AIFF mode saved music. Normal set up of optical digital output is 44.1KHz/16bit, though using MIDI setup in Utility folder, it could be set to 24bit/96KHz digital output mode. Thus MacBook tunrs to be a genuine 24bit/96KHz digital CD transport. Then hooking an external DAC (24bit/96KHz) to this port through an optical cable, MacBook and an external DAC will play a role of a high end CD player. Furthermore, when inserting a upsampling device from 96KHz to 192KHz, then it would give a higher resosution audio than usual.

Is there anyone who has experienced the same as described ?

Question is, as compared to a regular CD player with a upsampling DAC externally hooked, MacBook internally upsamples an origianl 16bit/44.1KHz digital audio to 24bit/96KHz. I am curious on the argorhythm to upsample inside Macintosh. Please note that MacBook provides Intel qualified high end audio sound borad by Sigmatel, which is compatible with Windows PC.

Any comments are welcome.

I do not hear any big difference between this and the sound out of a regular CD player such as Accuphase DP-85, Northstart 192MK2 with an external DAC (both are 44.1KHz/16bit)