When the wireless connection on, I can not always shutdown my computer, always it stoped at the ubuntu interface. But if I use "sudo ifconfig wlan0 down" before shutdown, it will not happen, is there something wrong with the wireless dirver? 03:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter (rev 01) 09:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 03)