IdeaVim j and k behavior on OS X

Dumb question...  When I use IdeaVim on my air book, the j and k keys don't "work" if you hold them down....  for example, on my windows machine, if I hold down the j key, then the cursor moves down the file one line at a time.  If I try the same thing on my mac, no luck.  I have to keep pressing the j key repeatedly to move down the file one line at a time.  

The k key has the same behavior.  I've tried the plugin on AppCode and it has the same "issue".  I've tried using all of the available key bindings, but I can't get it to work.

User error or known bug?  

thanks,

John