Hello-

For some strange reason, my N9 recently stopped detecting my headphones when I plug them into the phone. The issue isn't isolated to specific set of headphones, so I know the problem lies with the phone itself. I checked to make sure there wasn't any dirt or dust in the headphone jack. I'm hoping this isn't a hardware issue. Does anyone have any ideas? Thanks in advance.

-Sincerely, bobofosho123

Do the original headphones work with your N9?
Maybe this thread will help you out: http://talk.maemo.org/showthread.php?t=85310

Try to reboot phone with headphone plugged in. Remove earphones and see if loudspeaker works. If it doesn't, take phone to Nokia Care.
Same problem after i 'ahem' banged my phone into a table.. Nokia Care replaced the motherboard and everything is ok.

quite many headphones are not compatible by default, but usually if you plug in a suitable adapter cable they start to work. Like my AKG K540 is totally silent when plugged in with its standard plug http://fi.akg.com/akg-tuotteet-detail-fi/k450blu.html but if you add communicarion kit cables http://fi.akg.com/tl_files/catalog//...English%29.pdf you get adapter cable that works with N9. Kit includes adapters for nokia, blackberry and iphone.