I did some research into my new computer, (one of the new Mac Minis) and found that the 3.5mm audio jack supports both analog and digital audio through the copper interconnect from this page as well as a tiny optical port.
The format of the digital audio out might be different than S/PDIF Coax though ... I'm not too knowledgable about audio, really. Any ideas?
The type of the cable is irrelevant. Digital or analog is the amplitude output type. Digital outs can be of toslink/coaxial/stereo-mini in nature.
I'm not familiar with Apple products, and have never heard of a combined digital and analog out. Only thing I can think of, find out where the audio properties are for your Mac Mini, and select SPDIF bypass output.