The Dropped Connection
Bluetooth connectivity on Linux has improved dramatically, but aggressive power management can still cause headaches. Ubuntu uses the BlueZ protocol stack to manage Bluetooth devices. To conserve laptop battery life, the system may employ an auto-suspend feature for the Bluetooth radio. If you leave a Bluetooth mouse idle for a few minutes, or pause music on a Bluetooth headset, Ubuntu might automatically power down the Bluetooth adapter. When you try to use the device again, you experience a frustrating delay as the radio wakes up, or worse, the device drops the connection entirely and forces you to manually re-pair it.
Disabling Bluetooth Auto-Suspend
To stop Ubuntu from automatically disconnecting your Bluetooth peripherals to save power, you must manually disable the USB auto-suspend feature specifically for the Bluetooth controller module.
You need to edit the GRUB bootloader configuration to pass a kernel parameter that disables Bluetooth power management. Open your terminal (`Ctrl + Alt + T`). Run the command: sudo nano /etc/default/grub. Look for the line that starts with GRUB_CMDLINE_LINUX_DEFAULT. It usually looks something like `=”quiet splash”`. You need to append the `btusb.enable_autosuspend=0` flag inside the quotes. It should look like this: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash btusb.enable_autosuspend=0". (If you have other parameters in there, just add this one to the end, separated by a space). Press `Ctrl + O` to save, and `Ctrl + X` to exit. Finally, you must update the bootloader for the changes to take effect by running: sudo update-grub. Reboot your computer. The Bluetooth adapter will now draw continuous power, preventing idle timeouts and dropped connections.