Headrest slipping down from higher settings.

[4.8ISInCanada]

Ok, my dealer is 2 months out for an appointment, even though I told them this is a driver safety-issue. Also I am a long ways away from my next service appointment so the question is:

Does anyone else have a headrest that does not stay up at the higher settings (top 2 notches)? If so, did you find a way to fix it? This might be a common problem, or maybe its just mine. I will probably swap the drivers/passenger head rests tonight but not all my passengers are short so thats not a permanent solution.