Same issue with precision M4400. The internal mic worked on a clean 9.10 install but external mic would not. The only way to get the external mic working is to run alsamixer and change the digital input to analog. To revert to the internal mic I have to run alsamixer and set the digital input to digital mic.
Same issue with precision M4400. The internal mic worked on a clean 9.10 install but external mic would not. The only way to get the external mic working is to run alsamixer and change the digital input to analog. To revert to the internal mic I have to run alsamixer and set the digital input to digital mic.