Two weeks ago, my MBA didn't make any sound and he didn't find any output devices. It was solved by resetting PRAM. Today I have the same problem, but the reset doesn't seem to work. If I restart, I get a black screen, normal screen , black screen and so on. When I check by hardware -->audio: it says audiocode:0 Could it be possible to solve it or not? And if not, could a usb sound card be a solution? Thanks!