Letter keys don't work with Flash.
The letter and number keys on my keyboard don't work when i'm playing Flash games. The arrow keys, shifts, spacebar, etc. all work, but the first letter or number that I press gets stuck down (functions like I was holding it down) for ~ 10 seconds, and then none of them work after that(even once that key is no longer acting as if it was held down).
Alla svar (1)
So i just had this exact same problem and worked for hours to find the answer. Space and arrow keys worked, but letters only worked one time. I bought a Lenovo Laptop that came with the program "GuardedID" pre-installed on it. It functions as a decoder for the keys when using flash based games and other things. So when i pressed the key for the first time on the games it would act as a number instead of letters, therefore making it not work. I searched on Lenovo's website in their forums and found the answer to be "delete GuardedID" It has an error in the program. I deleted it and my keys worked immediately in flash games. So if you have a program called "GuardedID" the answer will be to delete it. or if you have a similar program that changes your keys to a different code while on the internet, you need to get rid of it.