Worked for me after I changed the ssd to SanDisk SSD PLUS 240GB and extern USB-controller ELUTENG USB 3.0 to SATA Cable 5 Gbp/s, UASP SATA . I used the original ubuntu 20.4 - server - pi image from raspberry.org download-page and made complete setup on ssd-card. Afterwards I made an image and imaged...