I have some problems with my mathematica 10 on Ubuntu 12.04. First, the keyboard input is extremely slow. I press a key, and then the input comes with a delay. This makes typing very cumbersome.

However, this is not the biggest issue. After a short while, my keyboard goes mad and the keys get shuffled around, so sometimes when I press a key, I get a different input (however, the delay issue is now gone...). Some examples, now every 4th keystroke I get "g" for ~4 keystrokes, no matter which key I press. Another time, every ~8 letter keystroke was ignored, while every ~4th arrow keystroke gave an "s". It is completely absurd. The "random input" seems to depend on what I previously typed, in some way. I tried to upgrade from Mathematica 10.1 to 10.2, but no improvement.

Anyone has similar issues?