This model seems to have an issue whereby the disc tray won’t open, even if the front panel flap is correctly open. You press the Open button and nothing happens, though on the screen it’ll say Open.
Some recommend putting it into Standby mode (off) then holding down Stop and Channel Up. That didn’t work for me.
Putting it in Standby and holding down Open did work… it first started up, then after about 10 seconds, the disc tray opened.
(Possibly it needs a firmware upgrade… I’ll check that out eventually, though it’s not my unit.)