I got called back to a house after the other sparks had finished with led fittings in a hall glowing when switched off. The other sparks before me told the owners there was interference on the 2 way switching so chased out the walls and fitted new 3c+e pvc/pvc. I turn up and sure enough flick the switch lights come on full brightness, turn the other switch off and it just glowed, wouldn’t have noticed it in daytime but at night it would be annoying. Tested cables and there was voltages present, took lights off 2 way and they switched on and off no glowing. So I ran out a new length of cable through hallway as I had place to myself and connected between switches still did same thing as before. Scratching head time now so went out to van and grabbed another 2 click mode switches. Tried replacing a switch at a time didn’t make a difference. Still had my temporary 2way cable so it couldn’t be get any interference. It must be the switches even though I changed them both already. Went out to van turned it upside as I wanted a different make switch this time as I wasn’t sure the click ones where truly switching even though they did according to 2 different meters. Found 2 Crabtree switches and whacked them on my cable first, switched on and off no glowing, fitted onto the newly replaced cable chased in the walls worked perfectly. The other sparks had wrecked this blokes hallway fitting new 2way cabling and didn’t cure the issue. I get to the bottom of it and solve it yet I am the one looked at in disbelief when I say you can’t rely on the click switches.
So just thought I would pass this experience on if anyone encounters led lamps glowing when turned off.