We've just fitted a some energy saving bulbs- the sort that fit an ordinary bulb holder and have a group of about seven glass cylinders forming the "bulb". They work OK but we've notice a dull "flash" about every 30s when 2 of them are turned off.
We've fitted six in total, 2 in table lamps (no flashing), 4 in bedrooms, only 2 of which flash.
I've not tried swapping bulbs between fittings yet but I am intrigued by the mechanism.
Any ideas?
Brian