So, I did this test for intermodulation http://people.xiph.org/~xiphmont/demo/neil-young.html#toc_1ch
There are simple audio files with a high sample rate, Playing those with the regular Windows player, with K-lite codec player or in a Cubase Session (96Khz) I get clicks.
In the website says:
Assuming your system is actually capable of full 96kHz playback [6], the above files should be completely silent with no audible noises, tones, whistles, clicks, or other sounds. If you hear anything, your system has a nonlinearity causing audible intermodulation of the ultrasonics. Be careful when increasing volume; running into digital or analog clipping, even soft clipping, will suddenly cause loud intermodulation tones.
What make sense, if the UR824 upper filter attenuate frequencies about nyquist in a correct way it should NOT make any sound… don’t?