To add to Sean's explaination, toslink is an excellent connection in THEORY. Problem exist on the receiving end of the DAC whre the optical receiver cannot cope with the bandwith and speed of the optical transmitter on the transport end causing a time delay in converting the optical signal to electrical.
This time delay or rather time error is what causes jitter. ST glass is another story much better than the Toslink.
This time delay or rather time error is what causes jitter. ST glass is another story much better than the Toslink.