There is a known issue with the Apple provided built in macOS Ethernet drivers for the Realtek RTL8153 USB 3.0 Ethernet chipset used in our dock (and many other docks and USB Ethernet adapters on the market). When put to sleep, the problematic driver creates an Ethernet broadcast storm which can overwhelm some Ethernet routers.For macOS Catalina 10.15.x users, please contact us via support@plugable.com and we can provide you with an updated driver and installation instructions.For macOS Big Sur 11.x users, this behavior can be rectified by updating the host system to macOS Big Sur version 11.3 (released by Apple on 4/26/2021).If you are unable to install third party drivers for macOS 10.15.x or are unable to upgrade from macOS Big Sur 11.x to 11.3, we recommend to disable your Mac from sleeping to prevent this issue, or use WiFi instead of Ethernet until you are able to install the driver at a later date or upgrade to the new macOS version.If you need further assistance feel free to contact us via support@plugable.com and we'll be happy to help!