Some news on this topic
check for WKC errors and diagnosis in the EtherCAT Master
seperate EtherCAT devices to own sync units
check in the EtherCAT Master CoE Object the WKC object in the "Slave Diag Object" the "Cyclic WKC Error Counter" for each sync unit, when it is incrementing a EC device is forcing it
when it comes from the ctrlX Drive try to adjust the Bus Sync Offset from 30% (600µs) to 60% (1200µs), e.g. for 2ms cylce time
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