not my experience at all it has worked since the day I got it doing output of DDL or DTS connect over SPDIF to my Logitech Z5500 - i assure i have no alog cables connected at all
maybe your confusion is you have to (confusingly) pick speakers as the output in window - but it routes that over spdif (not the speakers, yeah, i know it makes no sense, lol, here is the screen short with the confusing instructions) basically speakers is the whole device - i have no idea why they did it this way.
I also recommend this if using the SBZ
nicojeske/MasterVolumeSync (github.com) and this is good for anyone else who wants SPDIF to never truncate sound
Sound Keeper v1.3.0 [2022/07/28] — VEG.BY
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