Game Pickup's not moving

[rushin]

I'm having problems with some pickups in my game. Some of the pickups don't scroll with the background like they should. The code I have for scrolling is simply if the player's x coordinate is greater than 350 then the x coordinates of each pickup should decrease by 10 therefore allowing it to scroll. The code is as follows:

if (_x > 350) {
_parent.mainBackground._x -= 10;
_parent.crack._x -= 10;
_parent.beerPickUp._x -= 10;
}

It works on the pickups at the start of the game and a few near the end, however, the ones in the middle aren't moving. Therefore the player never sees them to pick them up. I have the instance names correct, and even if I drag a new movie clip from the library on to the scene and give it the instance name beerPickUp, it doesn't work. Can anyone shed any light on this?

thanks in advance
rushin