I am not declaring that Schitt's product does not work at 192K. They are competent designers and if they say it works at 192K I would believe them. When we did the Bottlehead DAC several years ago John Swenson mentioned that at that time TOSLINK might, theoretically, work at 192K in some cases but that in general at that time it did not. Bear in mind that both the optical transmitter and receiver need to be 192 capable. A lot (maybe all?) of older MACs that have TOSLINK are limited to 96K at the TOSLINK port, and a lot of older DAC receivers are as well. So there are a lot of setups around that do not work at 192K.