S/PDIF over mini TRS jack
The S/PDIF data rate is 3.072 Mbps max (@ 48 kHz sample rate), and with biphase encoding, that means an analog bandwidth that's also around 3 MHz. At these frequencies, and given the maximum cable length of ~10m, the small impedance "bump" created by a TRS connector is really not going to cause any noticeable problem.