I have recently purchased LED lamps and magnet attached circular units to replace old fluoresent tube units. The individual lamps in the format of a standard 240v lightbulb are no problem. But the circular units and two flush mounted down lights remain permanently slightly lit when turned off. One of the circular magnet attached units in particular is visibly lit in daylight. The remainder can only be noticed at night. I have tried reversing the wiring but that has no effect. There is no earth/ground wire. To check for earth leakage via the lamp body (which is fixed to the ceiling to an all steel framed building) I put insulation tape under the magnetic mounts even though the lamp unit is powder coated. This made no difference. There are no dimmers, only simple mechanical switches. The only way to fully kill them is to switch off the main supply. Am I missing something obvious ?
You will need to change out the LED's for a better model light or add in a real ground. Changing the LED's is cheaper and easier.
Did you leave the Florescent Assemblies in place with their transformer ? Or did you remove that ?
I have experienced this in a ceiling fan unit that had a remote control even some to be as bright as 50%.
I have also experienced this by mismatching LED's on the same lamp assembly:
LED's and Compact fluorescent bulbs.
LED's from one manufacturer with LED's from another manufacturer.
In all of the above cases changing the LED out for a different manufacturer fixed the issues. I now use all CREE or all Philips in my lamp assemblies and I have no issues.