lost sound yesterday

[funnyface2]

i'm newer than newbie, do apologize....i have win xp and ubuntu. i have sound on win but since yesterday on linux i get no audio channel....remember KISS principle ....i am clueless.....thanks

[kostasan]

Open a terminal and type alsamixer. Check if the two left channels are very low and raise them. Press Ctrl+C to exit alsamixer.

[funnyface2]

thanks, i have sound

[1fastbullet]

Up until a few days ago I had sound working fine. Then suddenly it faded to a whisper and now there is no sound at all.

I opened Terminal and entered alsamixer, raised all levels that would respond. The attachments are what alsamixer looks like. For some reason, the first bar (headphones)will not respond. The second bar (PCM) seems to be missing the bottom component.
On the extreme right side of the page are 3 input sources. The options in each of these are Mic, Front mic, Line and CD.
Which of the options should be set here to play music from the optical drives or from HDD?

Additionally, I used the terminal again and entered alsamixer -h and man alsamixer. The manual and "help" file were no help at all. Is there somewhere else I can find user instructions for alsa?

Can anyone suggest where the problem is and what will fix it?