Just an intuition (probably wrong) but I'd try this:
Find the boot options in the bios and turn CD rom booting OFF.
Then boot up as normal, into an OS of some sort, then shut down and complete power down.
Then go back into the BIOS and set CD rom booting back up again as you desire it.
Then after another power cycle, see what happens.
- Probably won't make a difference, but it's what I'd try.