@Stanislav I updated your post with your config.g and homea.g, to make it easier to read.

Could you try with the debug logging turned off? Comment out the following lines in config.g, save, then restart:

M929 P"logs/eventlog.txt" S1 ; Log WARN level events to logs/eventlog.txt M929 P"logs/infolog.txt" S2 ; Log INFO level events to logs/infolog.txt M929 P"logs/debuglog.txt" S3 ; Log DEBUG level events to logs/debuglog.txt

My guess is that all the logging is taking up too much time to service requests for file lists from the PanelDue.

It's possible there's an SD card issue; please run the tests described here: https://docs.duet3d.com/en/User_manual/RepRapFirmware/SD_card#troubleshooting-sd-card-issues

Ian