hifi engine

Nad L40

anybody got service manual/schematics for a Nad L40?
The problem is as follows:
CD tray opens (and shuts) randomly when receiver is switced on. Calmes down evenyually, tray opens when pushing button and display says open, but shuts imidiatly. When in shut position it says close in the display. No respons when trying to pres play.
I'll hand it in to an expert tech if I can get hold of a service manual, the local Nad shop can't fix.