On original factory fitted D3S bulbs, done 107K miles. Observed early this morning, the right shut off as it should, but the left remained on for about 5 minutes. Left has a redish hue and right blueish. Have ordered new Philips replacements so perhaps this'll resolve this issue otherwise, thoughts?

 

I've replaced them both. We'll see if that fixes it. The Osram XENARC originals were in well used condition.

 

New lamps fitted and problem solved. Also amazing how much brighter they are now.