If it has been sitting in someones basement/attic for all these years it has been subjected to many seasonal thermal cycles. It definitely possible the ROMs could have creeped their way out of the sockets causing some kind of weird ROM error.

Give the old Apple III method a shot

If I'm reading this correctly:

http://support.apple.com/kb/TA46376

It failed the memory test, most likely due to a chip that has crapped out.