Comment 114 for bug 477226

Assuming I have exactly the same problem (I have a Lenovo 3000 N200), upgrading to Maverick has improved things for me.

When I plug my headset in now, the front speakers are silenced. There are only two situations where this doesn't work:

a) If the headphones are already inserted when the machine boots
b) If the sound is muted when the headphones are inserted (i.e. plug it in, turn up the volume and it'll play through both)