Very low volume from headphones and external speakers on HP p7-1235 (Ubuntu 12.04)

Installed 12.04 on a new HP Pavilion desktop p7-1235 (AMD A8-5500 APU). Volume is very low from external speakers and headphones plugged into the front jack. I set the master volume and speaker/headphone volumes to max, but volume is very low. Used alsamixer to set everything to max, unmuted, same result.

Try installing pavucontrol:

sudo aptitude install pavucontrol

It might be that an output device has its volume low and the volume indicator doesn't control it (i.e. when you increase/decrease the volume, this only affects one sink only)

There's a chance that your sound card might not be driving enough electricity to up the volume. If it goes lower when you reduce it, this may be a good indicator of that.

The best suggestion would be to get a set of externally powered headphones/speakers.

Source: I had an HP DV-9000 with the same issue about 2 years ago.