This has also locked groove in the end of b-side, although itīs not mentioned in discogs sites:
http://www.discogs.com/Liimanarina-M...elease/1365090
It is some high, tight noise, like from some old doors hinge.
I listened the end of Unknown Pleasures & didnīt hear anything. I have half-automat record player, so itīs possible there is something even the spine went in the very end before it rised.
I have Canadian-version of Skyīs Gone out and there is no locked groove. There is just some talking in the end of the b-side before spine go to the runouts. Discogs doesnīt also mention any locked grooves in UK or US versions.