Window glitches and lost audio
I've been running Ubuntu 12.04 since my nephew suggested it a year ago. My computer is a Lenovo Thinkpad X61. One day as I was attempting to stream a video, it began glitching. The video was running in stop motion, and the audio would echo, then get caught on one sound which would repeat. I stopped the video and came out of fullscreen only to find the control graphics were not on my screen. No launcher, no window controls, nothing! Just my wallpaper and the window contents, that's it. So after trying all I know, I manually resarted my laptop. The problem occurred again, so I got fed up and shut down my laptop.
A few days later, I tried again only to find my laptop is running the videos just fine, but there's no audio not even from headphones. The graphic glitches now only happen on occasion but only when moving windows between workspaces. I tried opening Terminal and used 'alsamixer' command as the forum suggested and found something I don't think I should have seen (see screenshot). My sound cards are recognized and there's nothing wrong with my hardware.
Note that the sliders for both the headphones and speakers are missing, but neither is muted.