rega planar 2 foam piece in motor housing?

I have a used planar 2 and in looking inside the motor housing found a piece of foam that bordered two sides of the motor. I'm assuming this was to keep the motor centered when active, but wasn't sure if this was standard or added on by the previous owner. Anyone know the answer to this? Thanks in advance.
This has been heard of,there are after-market mods for Rega motors that do this,try it out and see if it works effectively....or not.