player blinking all over the place

[Jon]

I put a Player on a main stack.  I then put a few tables and a button.  
Often when I switch back to the stack, in design mode, the player starts 
flickering like mad, and all of Revolution stops responding for a 
while.  If I switch to another task and back, the Player settles down.

Any clues as to what is going on, and how I can make the Player settle down?

:)

Jon