This worked Here is a technique that sometimes works:

gksudo gedit /etc/pm/config.d/config Add a single line:

SUSPEND_MODULES="r8712u" Proofread, save and close gedit. Reboot

description: Wireless interface physical id: 1 bus info: usb@2:6 logical name: wlan0 serial: 68:a3:c4:79:51:3b capabilities: ethernet physical wireless configuration: broadcast=yes driver=r8712u ip=192.168.178.30 multicast=yes wireless=IEEE 802.11bgn