D1 dimmer flichering my LED lights

Do you have a RF remote paired to the dimmer?
As you may be aware, the dimmer enters in RF Pairing mode as soon as it is powered on. If you get power outage and when power is restore, it can cause the dimmer to get paired with a random RF signal that my be present at that time (e.g. your neighbour using a remote to open his gate!) and then the light will switch on at any time the same RF signal is received.
Solution is to clear RF pairing on your remote and pair again.