If I can pinpoint the issue if it's related with router itself, it will be really helpful. Edit: I also tried to hard reset modem entirely, still same.

@Beholster Thank you for help, I check all house infrastructure in weekend, Normally, when touching the splice points in the cables or bending the external cable, a change in the attenuation value...

@Joseph-TP Joseph-TP wrote Hello @Beholster , Welcome to our community. For the DSL Line Quality and CRC Errors: 1. Enable SRA (Seamless Rate Adaptation): Log in to your router's management page via...

Also I'm on a 100 Mbps plan in VDSL, but I'm only getting around 35 Mbps download not even half, even though my upload and ping seem fine. I forget to add that.

For the past four months, my router has suddenly started getting an absurd amount of CRC errors, and I’ve lost almost 80% of my speed. I contacted my ISP, but they completely ignored me for three...