Rutx50 has become unreliable

This could indicate that the internal modem has stopped responding. I will ask you to wait for the issue to replicate, then navigate to System → Administration → Troubleshoot, press SHOW button on the System Logs, and copy the logs from when the issue started. It can either be pasted into the next comment, or attached as a file. Please remove any sensitive information from the logs!
Additionally, could you clarify how the information from the screenshots was collected?

Best regards,

Yes i will take out the logs when i can access the router locally.
Data is from your own RMS system, I did an export to csv-file.
You can also see at the diagram a small drop out from the night before, lasted 1min, drop also confirmed by my other hardware.

Thank you for the information.
Please create a separate issue when you manage to gather the logs to avoid spamming all other users and I believe this may be a separate issue.

Best regards,