I supposed that my T40’s built-in microphone was ruined(for this is a second-hand thinkpad). But accidentally, I found it works well…
And here are some tips for laptop’s built-in microphone on KDE(KMix):
1. You can test if you microphone works by click the green point below the mic icon(Input tab) to make it light and connect the input of microphone to speaker, then flap your Mic. But be careful, if you use built-in speaker, the treble voice would be generated if you adjust the volume to more than level 3. So, in the normal use, please close the microphone output to speaker(except you use headphone).
2. You can enhanced the microphone output. Click Switches tab in KMix, and select Mic Boost +20dE. But don’t make microphone connect to built-in speaker with this.
3. If you still not content with the result, you can set the Capture of Input tab to maximum.
4. You can also use vumeter -r to see the recode volume level.
I got very perfect result with disable Mic to output, using Mic Boost and using built-in speaker.
Good luck!
Thank you. It works. Make sure that
Mic, IEC958 (if you’ve got that) and Capture in Input Section are all at max and light-colored (not dark)
two-hand…