[ubuntu] My internal microphone doesn't work on my Toshiba laptop anymore

I searched for this issue all over the Inteet, found many solutions but non of it worked for me. So, my Toshiba laptop can NOT record any sound anymore. I recently upgraded to Ubuntu 16.04 (dual boot with my Win7 Pro). My inteal microphone perfectly works on my Win7 Pro system on the same laptop, but it doesn't seem to work on my Ubuntu, no matter which application I try. I can hear the sound, so the output audio works with any application. Here's a screenshot of my input audio settings (image attached)...

Any hints?