Of course this is annoying.
You can try the latest driver-package from http://wireless.kernel.org/en/users/Download (linux-stable backports releases)
And the latest Firmware from git
sudo apt-get install git git clone git://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git
The appropriate files in /lib/firmware must be replaced.
Test some driver options:
disable hardware encryption
echo "options rt2800pci nohwcrypt=1" | sudo tee /etc/modprobe.d/rt2800pci.conf sudo service network-manager stop sudo modprobe -rfv rt2800pci sudo modprobe -v rt2800pci sudo service network-manager start
(typo corrected)