When that first happened to me (and it did the FIRST 2-3 days I purchased the car), I rode around, and pressed the eject button a few times, and I actually hit a bad bump and it popped back in place somehow.
If you have enough patience, you can disassemble the deck and put it back in-line. Like I said, I occurred on me the first few days of owning the car, and about 2 days before I was to return to Lexus, I hit a road bump (a slight one) and I heard my cd player kick on for no reason. From that day on, it never broke again..... I tried to duplicate it quite a few times to make sure it doesn't happen again, and it never has.... gl!