To be clear, GerdGarten... I think there is a problem in the way MC handles Exclusive vs. Non-Exclusive mode on OSX in the current version. As I said above, it should be returning the system sample rate to the original setting when Playback stops, and it seems like (in my brief tests) that it is not.
That's bad, but it does NOT impact your ability to use your HiFace at the 192kHz sample rate you seem to want it to use. You have MC set up wrong if that's what you want.
Now, it could be argued that what you want is non-ideal (it is generally recommended to preserve the original sample rates). However, ignoring that, if you want MC to resample everything to 192kHz, you can absolutely do that, you just don't have that set on your copy. MC does not use the system resampling engine and does not obey the system sample rate setting. It has its own internal high-quality resampling engine.
These internal resampling settings are found in the Output Format DSP, as 6233638 pointed out above. If you want MC to play EVERYTHING at 192kHz, you have to set it to resample everything to 192kHz.
So, if I'm right and it was working properly, fixing this wouldn't directly impact your issue, which is due to a misconfiguration. The way it should work is:
* If Exclusive mode is enabled, then all files play back natively, and the system sample rate setting is bypassed (or set to 44.1kHz and then back to the original setting automatically when playback stops).
* If Exclusive mode is disabled, and the system sample rate is 192kHz, then your playback should FAIL if you try to play something at 44.1kHz. Then you'd HAVE TO enable the DSP resampler to get anything to work at all.
This is how it works on Windows, and I think is how it should work on OSX, but I'm not 100% clear on the meaning of the settings in the OSX Audio Midi Setup application. I did test it with other applications though, and they seem to preserve the setting in there (which means if you play a 44.1 source file, then it MUST be resampling the file, or ignoring the setting). MC changes the setting to whatever format you last played. I think that's right, but it should put it back when it is done.