Same here, it’s been doing it for the last two weeks. It was unplayable as you couldn’t progress because it would rubberband into a group of enemies or would freeze for a few seconds and all of a sudden die. I was connecting though 5ghz network getting 247Mb a sec and tried everything even all of blizzards “troubleshooting” and today I switched to 2.4Ghz getting 63Mbs a sec and WHAT? The lagging stop. Been playing all day no issues but really blizzard really punishing people because you can’t handle high speeds. Get your diablo together.