Microphone vs. Desk Latency

I just thought about this issue I focus, but i do not find a possible solution. Maybe you have some ideas:
my System:
Ubuntu Studio 20.04LTS running on HP Laptop 8GB/i5 3.2GHz. Steinberg UR22mk2 usb audio
Mixxx 2.2.4
Using Jack Connection Kit with Carla.
From the UR22, i use the input signal and route it thru some plugins on CARLA before i go into Mixxx Microphone input ports. This will give me a latency of around 200ms. Now i have always a delay in the Micropjone audio.
Is there a way to have the Desks delay the audio output for the internal mixer? i see only a delay for the master/booth output… But this will not help, because it increase the sum only.
Any Ideas?

Yes, this is exactly what the microphone latency compensation setting is for: 9. Using Microphones — Mixxx User Manual

Thanks. Yes, I had issue to understand the manual… thank you for your assistance. I need to check this once i find some time.

Okay, I setup like described in the manual, but no luck. Still have the latency in my recording.
So i first checked the Round Trip Latency, which was 114.650ms (with setting the knob on the UR22 to DAW). I put that value into the Microphone latency compensation field, I switched to direct monitor in mixxx and set the ur22 on input mic to UR22 ch1. In Mixx the Headphone output is set to ur22 output channel1+2. The Knob on UR22 is now set to the middle. I Still have the delay in the recording.
Maybe something is missing?

Okay, I guess I need to check the latency again… I get the following:
5057.427 frames 114.681 ms total roundtrip latency
extra loopback latency: 5057 frames
use 2528 for the backend arguments -I and -O
Does that mean i need to calculate the 2528 in additional to the roundtrip ?

No, that number is for setting the -I and -O options with jackd. Even if you do that, Mixxx does not use the values from JACK.

If the plugins you’re using outside of Mixxx add latency, then you’ll need to measure the latency of that whole setup. jack_iodelay can help.

I have measured without any plugins so far, I am aware that the plugin would add that and i need to adjust. Currently only Mixxx is connected between the UR22.
But in general, if i add that I and O to the jackd and mixxx does not take this into account, i will have the delay. As far as I understand (What I have read so far), these frames are the delay for the I/O process.
So if these 2528 Frames in not include into the roundtrip latency, I have to add them, right?

You’re misunderstading. Some JACK programs use those -I and -O parameters to compensate for latency. Mixxx does not because those values aren’t exposed by PortAudio. Instead Mixxx has the “Microphone latency compensation” configuration value.

What does mixxx do in case of the setting of 114 ms? Does that mean it delay the Deck for that time to be in sync with the Microphone signal? If this is the case, then i still have the latency which the sound takes from mixxx to the Headphone which is plug in the Soundcard, right? So if i listen to a song played in mixxx and record me singing the same song, it will not work, because what I hear has the delay from the computer to the soundcard.

Yes, the main mix is delayed before the microphones are mixed, then that mixed signal is sent to recording/broadcasting.

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Alright… Okay… But i got now the point. I did the following… checked with and without setting a delay… and i saw that the delay was reduced adding the delay… with the setting around 114 from the loopback measurement, i still got a delay in the recording, so i had sing synchrone and checked in audacity the delay time which I added tho the latency value which makes it now nearly correct… i now have a delay time of 160ms… So problem is solved, thanks Be0… So this shows me that i had to add around 50 ms , which is have of the overall measured delay. So from this I am not sure if the dynamic microphone has a short delay as well or where it came from…