Thanks for the reply. Yeah, this thing has been with me for 3-4 years, and the cable has been subjected to some abuse. Nothing's really visibly damaged, but it doesn't need to be.

https://gtm.steamproxy.vip/discussions/forum/11/4932019356819019755/ it can be a cable - at the base of the mouse, one of the wires breaks and the contact is interrupted when the mouse is moved - now many wired mice do not use pure copper wires (vzurbt), but an alloy with aluminum, which is brittle
I have the original MX518 - still works perfect and the wire is soft. and there are G400s - the wire became brittle and brittle two years after the purchase and had to be replaced (cut off the damaged area and soldered to the cable) + the buttons work worse. +Recent Win and Steam updates broke a bunch of things - people are complaining about problems with USB, WiFi, VPN, DirectX9