Ok… hear me out.
I purchased the Uniti Atom around June 2018. I hooked my PC up via optical. The Atom supports 24bit/192kHz ON OPTICAL (dont ask me how that is possible) so, of course, i was running 24bit/192kHz.
After one year or so, i began to hear loud cracks and distortions when i was running above 24bit/96kHz. I tried another cable of the same make (Goldkabel Profi Line) and switched inputs. Sound was normal again. But when the distortions reappeared i did the same as i did before.
After several repeats i noticed, that one of the input would not hold the toslink plug tight enough, so it could easily be pulled out. On inspection i saw the nipples inside the toslink input been worn out. Also the distortions wouldnt go away either.
My Atom is in service for more than two weeks now. And on request, they told me everything was ok and nothing has to be done. I told them to check again. Because on my loaner device (Primare I25 Prisma) i dont have distortions on toslink (supports 24bit/192kHz as well). And the plug sits tight.