Choppy Keyboard Control

Hi I just set up this great emulator.

Unfortunately when using keyboard controls, holding down a key results in a 
brief pause, then continuation of the action.  For example, on Atari 2600 Demon 
attack, if I go to the left side of the screen and press a button to slide 
right, it will move a bit, pause, then continue the motion to the right side of 
the screen.  Is there a way to fix this choppy control?  Thanks!

What steps will reproduce the problem?
1. Run any Atari 2600 game where you can slide left or right across the screen, 
go to one side, and hold left or right to move to the other side
2.
3.

What is the expected output? What do you see instead?
Smooth movement across the screen, but there is a pause then continuation of 
the movement.

What version of the product are you using? On what operating system?
1.91

Please provide any additional information below.

Original issue reported on code.google.com by Todd.Kad...@gmail.com on 21 Feb 2015 at 4:56

Yekyaa- / bizhawk

Choppy Keyboard Control #398