Just a guess from someone who doesn't have an XPS but has experienced similar symptoms. Maybe there's some kind of debris or perhaps liquid in between the switc

Just a guess from someone who doesn't have an XPS but has experienced similar symptoms. Maybe there's some kind of debris or perhaps liquid in between the switch contacts for those keys. In my case, two plastic sheets comprised the contact surfaces and getting them separated and cleaning them with a damp cloth and drying them did the trick.