Could you access your router using http://192.168.0.1/ or http://192.168.100.1 for modem mode . Don't log in, select the 'Check Router Status' option and paste your 'Downstream', 'Upstream', and 'Network Log' tabs?
At least we can check the stats to rule out an issue with the line.
Hi Fila, thanks for posting and welcome to our community.
I am really sorry to hear of the packet loss issues you've reported. I would like to take a look at this on your behalf. To enable me to do so, I am going to send you a private message. Please look out for the purple envelope in the top right of your screen.