It is possible that the problem is the port, but try the following to get it to notice the headphones and then the second list for the mic. Yes I know it is a bit of a pain to have to check/do both, but that is how it is.
If your external speakers/headphones aren't working, try the following...
1. Go to "Control Panel".
2. Click on "Sound".
3. Make sure you are on the "Playback" tab.
4. Click on the device you are trying to fix.
5. Now click the "Configure" button and follow the prompts. (Be sure you also click the "Test" button.)
6. Once that is complete, click the "Properties" button.
7. When you are done with your changes, in "Properties", click "Apply" and then "OK".
8. Then click "OK", again, on the main "Sound window".
NOTE...