Simultaneous sound problem, Headphones and Speakers

[ShapeShifter499]

Hi, I'm having problems with sound, its playing simultaneously through both the speakers and the headphones when headphones are plugged in. The problem is fixed when I manually set "headphones" in Sound Preferences. However this is not done automatically, why? Can someone help me with this problem its vary annoying.


Computer Information

Aspire 7540-1284, AMD Athlon II X2 M300 Processor, ATI Radeon HD 4200 Graphics, 320 Gigs of storage, and 3 gigs of ram. Operating System Ubuntu 10.10 64 bit

[ShapeShifter499]

HERE IS SOME MORE INFORMATION ON MY SYSTEM


lance@lance-Aspire-7540:~$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: SB [HDA ATI SB], device 0: ALC888 Analog [ALC888 Analog]
Subdevices: 0/1
Subdevice #0: subdevice #0
card 0: SB [HDA ATI SB], device 1: ALC888 Digital [ALC888 Digital]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: HDMI [HDA ATI HDMI], device 3: ATI HDMI [ATI HDMI]
Subdevices: 1/1
Subdevice #0: subdevice #0