any differences if you use different optical output sources?

Hello, I have a question wanna ask you guys:


With a same DAC, same AMP, same Speaker system, same song, but if you use different optical output sources; for example: toslink from the mainboard vs from the sound card...; so they give you the same or different sound? I myself couldn't recognize any differences, but some say they could, and I wonder if they really do


Thanks