The other night I noticed a table lamp fitted with a "low-energy" lamp (one with three loops of glass) was playing up. It seemed as if the actual lamp fitting was the problem so, reaching inside the shade and carfully holding the insulated base of the map itself I attempted to press it upwards, to see if this fixed the problem (low light output and flickering). Anyway, no solution there. However, when I was moving my hand from the shade I felt what seemed to be a decent electric shock! I've had a few (E.S's) in my time so know what they feel like.
This however felt like shock + intense heat at a very small area. Purely a long shot but I wonder if the LL lamps have an as-yet unknown failure mode where by a "micro-pinhole" in the glass can provide a path to earth. I know friends, that this is downright wacky
- but that is what is felt like. It was a *very* localised pinhole type stab - and rather painful. No spikey glass bits seen on lamp.
Also, when I replaced the lamp (which I should have kept for investigation), with a brand new one, it worked just fine with NO changes to the wiring. Plus btw, no shocks when touching any part of it.