No, this is only the case on Babyface pro (FS). The UCX II has enough DSP power for processing all the effects internally.

Again: on the UCX II, the effects are processed on the internal DSP chip, so the PC's power is irrelevant.

Sorry for the long wait.
I will try to make another sample

It should be noted that the example recording made above is a highly increased volume section where I extract the sound with rather weak dynamics to hear reverb tail. 

Regarding your questions:
The dynamics/eq section is off
I was testing reverb with a microphone on the microphone inputs. The same situation is seen on the microphone and instrument inputs.
I can hear this effect when just monitoring the channel through headphones with reverb  and ucx ii in standalone mode without PC.

The recording was made like this: The cable goes from the guitar to the rme instrument input, the send fx fader is raised on the input channel (e.g. Analog 3), than choose adat 1/2 channel and raise analog 3 channel fader for direct mon., and also raised the fader for Fx return on adat 1/2 channel + enable loopback.
—The DAW is recording signal from adat1/2 to track.

I don`t know why, but this type of monitoring sounds a little bit different than direct Analog 3 channel monitoring  , but I can assure you that I hear exactly the same jet sound and noise level raising  when directly monitoring any input channel through the headphones with reverb turned on

The reverb jet noise doesn't respond to what I'm playing or what happening in my room. it's a strange sound that appears when the reverb tail modulates - phrase or word just had to be long enough to hear it completely.

May someone check reverb work on Babyface pro fs or ucx or other RME devices, please?
Any reverb type exсept "Space", any parameters,  better to rise up effect volume to 0 for better understanding where the artefact is.

Support tells it`s not high quality reverb and there is nothing to do with algorithms. But it`s not looks like just low quality it sounds good, but i can`t really hear  it work behind  noise that appears with enabling reverb in Total Mix. Noise that appears with reverb tail  audible even at - 10 effect volume. I can`t compare device with another one because they are out of stock in my country.

Thank you
I made one more sample it s shorter and more clear if you need.
First dry DI signal, than i activate reverb button in Total Mix. Total Mix settings screenshot also avaible
https://drive.google.com/drive/folders/ … share_link
LP guitar with humbuckers, fully shielded.

I'm sorry if I misunderstood.
Not intentionally. I just forgot to center the guitar when recording.   The previous microphone and guitar  test was done centered before recording. I put a stereo recording in studio one on the track anyway, to record the reverb as it comes from the total mix.
From what I hear on the last sample noise and artefacts are clearly audible,

upd
You`re right. Added stereo sample in mp3 and wav
https://drive.google.com/drive/folders/ … share_link

Same reverb/channel settings as on screenshoot in folder. But i think it was more audible in previous sample.

Thank you much for your time and test.

From what I hear, you have almost exactly the same situation - the addition of noise when the signal goes to the reverb bus.
So, this "hiss" that appears when you play notes and dissapears when you stop playing should not be present.  On my  Motu track 16 dsp reverb  It also have room reverb with few types of room. Just can`t find the way to record it as on rme to give an example what i am alking about. But i didn`t hear that kind of reverb work before on other devices.

Only the flanged artefact ( or idk how  to call it) is not really audible  in your example, maybe you just need to hold note a little longer

We are still testing. Please give us a few more days to come to a verdict.