I had similar problems.
this wireless card seems to try and use two drivers at once, so neither work.
open a terminal and
sudo lshw | grep RTL8192
you will probably get two drivers listed the E version and the SE version.
blacklist whichever you dont require in: /etc/modprobe.d/blacklist.conf
to blacklist a driver - again in a terminal
gksudo gedit /etc/modprobe.d/blacklist.conf
add this line to the end of the text file,blacklist <name of driver here>
eg: blacklist r8192se_pci
save and restart: