RE: Why do I need to replug my headphones every time the computer boots up?
Hello. Yours is the 3rd post I have seen about this problem, each time it is a different model but all have Realtek audio, so I think there must be a bug in the Realtek driver. I suggest that you install the native windows audio driver. If that fixes the problem then that would point to a bug in the Realtek driver. Afterwards you might want to try a different version of the Realtek driver.
To install the native driver, remove the Realtek driver. Open the Device Manager and expand the Sounds controllers section. Right click on the Realtek and select to uninstall. Put a check mark in the option to delete the files, and then ok. When you reboot, Windows will either install its own native driver or a Realtek driver if there were any other versions on the hard drive. So go back to the Device Manager and check for a Realtek driver. Keep uninstalling & rebooting until Realtek no longer appears under sound controllers. The name of the native driver will appear as "High Definition Audio Device".
To try a different version of the Realtek driver, go to the Realtek driver page for the XPS L511z and click on "previous versions". Pick one that is different from the one you have now. It is best to remove your current Realtek driver before installing a new one. It's okay to install a Realtek over the native driver.
Jim Coates -- 15 years on the Dell Laptop Audio boards -- since 2/6/04