Momentary stutter after adMob banner is displayed or during refresh

Hi there,

In test mode,  I am noticing a momentary stutter right after the banner is displayed or during a refresh after the default 60 seconds setting.  The stutter is brief (about a second or slightly so) , but it somehow affects the gameplay as the game is about precise jump timing .  When it happens, it affects the player’s ability to make precise decision to hop the character.  

The game has only one scene, and there is only one place i make the call to ad.show() and that is in the main menu.   The add will remain on screen and gets automatically refreshed after every 60-seconds.  It is during the display or the refresh that the stutter occurs.   The init() is also called once, in the main.lua.  

Is there any means to avoid this? 

Thanks.