Lately I've been getting this black screen at boot time with 2 lines saying

Checking media [Fail]

And the time of booting has extended greatly due to that thing (like from seconds to a minute)

I have a Dell XPS15 with SSD and I'm running Ubuntu 12.10 and it was not like this before. I don't have a clue what is it connected with - maybe it's due to a kernel update or something. And what do those 2 lines mean.