The Peripherals Disconnection Issue
In its quest to squeeze every last drop of battery life out of laptops, the Ubuntu Linux power management daemon aggressively monitors USB activity. If it detects a period of idleness, it will automatically suspend the USB port to save power. While this is fine for a thumb drive, it creates massive usability issues if you use an external USB hub to connect multiple devices like a mouse, keyboard, and external DAC. When the hub is suspended, all attached peripherals instantly die. When you wiggle the mouse to wake it up, there is a severe delay—and sometimes a complete failure—as Ubuntu struggles to re-initialise the entire hub and all its sub-devices.
Blacklisting the Hub from Suspend
To ensure your external USB hub and all connected peripherals remain constantly powered and instantly responsive, you must instruct the Linux kernel to explicitly blacklist that specific hardware ID from the autosuspend protocol.
First, you must identify the hub’s vendor ID. Open your terminal (Ctrl+Alt+T) and run the command lsusb. Locate the line corresponding to your USB hub (e.g., “Anker” or “Generic USB Hub”) and note the ID format (for instance, 2109:2811). Next, you need to create a custom udev rule. Type sudo nano /etc/udev/rules.d/50-usb-hub-autosuspend.rules and press Enter. Inside the nano editor, paste this exact line, replacing the vendor and product IDs with your own: ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="2109", ATTR{idProduct}=="2811", ATTR{power/autosuspend}="-1". Press Ctrl+O to save the file, then Ctrl+X to exit. Finally, force the system to reload the rules without rebooting by typing sudo udevadm control --reload-rules && sudo udevadm trigger. The kernel will now provide uninterrupted power to your hub.