PSP freezes when UMD tray is closed

[seriouslysilly]

Hi all,
Just have another PSP to bring up to the gurus.

Recently got this PSP and everything is working fine at first glance.
UMD drive can read games, memory stick reader works fine, and wifi works as well.

The problem arises when the PSP is turned on and an open UMD door is closed.  It will then freeze.
The only way I can play a UMD is if it closed before I turn the PSP on.
I am unable to close the UMD at any time that the PSP is on.

Any ideas?

Thanks in advance!!