Thank you Matthias.
A question about clock:

This is the setup:

8 ch preamp AES---->ADI-642 clock set to "AES"---->Micstasy clock set to "Option"---->HDSPE MADI clock set to "MADI".

In this case, is the clock generated from the 8 ch. AES preamp or is genearate from ADI-642?
ADI-642 takes the clock from the 8 ch. AES preamp and so generates a new madi clock?

So the 8 ch. AES preamp should be at the first place of the chain, because clock signal goes in only one direction. Is that correct?

8 ch. AES pream--->ADI-642---->Micstasy--->HDSPE MADI

not

Micstasy----->ADI-642 (with 8 ch. AES preamp.)----->HDSPE MADI

How can I use the clock signal of the Micstasy?

I also have an external clock geneator, but the 8 ch. AES preamp has only the word clock INPUT, (not OUTPUT). How can I send the external clock generator signal to the 8 ch. AES preamp (with 642)?
Can I use only the word clock input of the ADI-642 instead of the word clok input of the 8 ch. AES preamp?

Thank you.
I'm not sure about the clock quality of AES preamp. So if I use the external clock generator in this way:

Rosendahl CLOCK GENERATOR------>word clock IN 8 ch. AES preamp----->ADI-642 set clock source "AES"------>Micstasy clock set to OPTN (madi)---daw clock set to "Madi in"

the generator is the Rosendahl, but the MADI cable is used only for transport the clock. Therefore the ADI-642 can be used for transport an external clock signal to much distance, over the limits of the ext clock cable.