Try booting into Windows 7, then shutting down (do not use the “restart” option, or cut the power), then boot into Windows 7 again. This seems to be a known issue that impacts some systems due to a conflict between the way Ubuntu and Windows handle hardware. You have been able to fix it by shutting down from Windows then booting into Windows again, which is slow and tedious, but it seems to work if you really need to use Windows 7 with headphone functionality.
eAnswers Team
Try booting into Windows 7, then shutting down (do not use the “restart” option, or cut the power), then boot into Windows 7 again. This seems to be a known issue that impacts some systems due to a conflict between the way Ubuntu and Windows handle hardware. You have been able to fix it by shutting down from Windows then booting into Windows again, which is slow and tedious, but it seems to work if you really need to use Windows 7 with headphone functionality.