Hi @Andrea_Bassanelli ---- Thank you for the report and sharing your feedback with us, both are appreciated!
Moving forward, to help me better evaluate what could be causing this behavior, may I very kindly ask you to please provide me with the following:
A brief, but expanded description of your current setup, using this link as a guide.
A screenshot of the playback settings you are using with the M2TECH DAC.
I know from you report, you mentioned you receive this error message “every time”. Can you confirm if you make this observations with same the sample rate(s) each time OR would you say this is more general?
During your troubleshooting have you tired testing with another DAC mounted via USB, just to confirm if you are noticing the same behavior with Roon?