The culprit has been found, thanks again for the tip.
The process of elimination ultimately revealed, that it was the ASIO4ALL driver, so I cannot recommend this combination from my side.
The bizarre thing is, uninstalling this driver alone is not enough, the problems continue to occur ... You also have to uninstall and reinstall the Xmos driver afterwards.
Fortunately, there are no problems with WASAPI.
The interference when playing high data rates still occurs occasionally, but extremely rarely and I couldn't say, whether the cause might be Tidal or my not particularly high-quality Toslink cable.
As I have to activate the exclusive mode on Tidal, so that the transferred data rate is displayed, could this perhaps be the reason why, the sample rate automatically sets itself to a certain value!?