Interior lights acting weird
 

2004 boxster s 24K miles, new car for me, interior lights seem to be acting oddly, or maybe I just missed the obvious. When I shut off the car sometimes the door lights and dash LED lights stay on a long time. Sometimes just the dash, sometimes everything turns off as expected after 20 secs. or so. If I lock the car all the lights turn off. The manual says the car will shut off the lights after two hours to prevent killing the battery. I find annoying that I have to lock the car when it is in a locked garage so I don't have to hear my wife say; 'the lights are still on again'. Any Ideas?