Is it normal for the base of the bulbs (silver/white part) to be warm when the bulb isn’t illuminated?
I only just noticed this for the first time today.
Even in an “Off” state the power still flows to the circuits. The wifi in the bulb is still active waiting for the user to give the on command.
Bulb being a little warm should be normal. I hope the bulb is kept in a ventilated spot and free from Enclosures. Also make sure that the bulbs are not connected to any dimmers since these bulbs can only be dimmed through software.
Lastly check the voltage of the bulb and the voltage supply that it is getting.
In case you have any doubts it is advisable to check from the nearest service centre.