Okey I can't see restart now because internet is dropping to 0,1Mbits and I have to restart manually. :) CRC classic. Nice workaround. I tried for example this: Disconnect/Connect Absolute nothing....

@YNWA @naz_eg They think so "modem crashing" and CRC errors are two different problems. We will see. Now it is short time to say about result. We will see about modem crash. Only what I met today:...

@scoomby how AVM Fritzbox 7530? still fine? any CRC errors? if yes, how much?

I contacted my ISP O2 Czech Republic again and I asked them about diagnostic my DSL line. Respond: high modem error rate

@naz_eg Finally a normal-looking modem (VR2100) with good papers parameters and some problem it absolute ruin it. :(

I only sent message above this. Diff time 23 minutes. And starts weird situation with speed again: + 23188 CRC only 23 minutes: Again slowly droping speed from 50/5 (see downstream):