On 12/03/2011 08:05 PM, Tony Bernardin wrote: > Thanks for the reply. This change is happening all the time regardless > of if I have anything plugged in or not. > > I'm willing to accept that I might have a hardware problem. I don't > currently have a working windows to try it out under a different OS. Is > there a way I could debug this issue further, e.g., could I somehow > check the jack detection? Could I see the hardware events in some log? > What driver (kernel module?) is responsible for producing those events? > Would it be possible to try another driver? 1) You can test this by using the hda-jack-sense-test program. Download the "snd-hda-tools" package from https://launchpad.net/~diwic/+archive/ppa and run "sudo hda-jack-sense-test". Your headphone jack should show up, if not try to use the "card" and/or "device" parameters to find the right codec. If this is a hardware problem, repeated runs of hda-jack-sense-test will not always correspond to having the headphones in. However if the flickering is very fast (say 2 seconds off followed by 10 ms on in cycles) you might not be able to catch it. 2) You can also use the "evtest" program to check the kernel interface, but I'm pretty certain it flickers as much as the port change does. Does the flickering (i e switching back and forth) happen both if you have headphones plugged in and if you're having it unplugged? -- David Henningsson, Canonical Ltd. http://launchpad.net/~diwic