Microphone Audio Capture Very Faint

After installing skype (via Synaptic) I found that audio captured via my microphone (plugged into the external jack) was almost inaudible on playback. Ultimately, I overcame this as follows:

1. From the command-line run alsamixer
2. Select the "Capture" channel and increase the recording levels, e.g. 75/75
3. In skype select Tools > Options... > Sound Devices > Audio System to use: ALSA