I have been turning on and off an installation, including some LED PAR lights, using a digital timer switch (Brennenstuhl Primera Timer DT). It's been running since half a year or so, but recently I noticed when all lights were off and the timer was in 'auto off' position, that the LED PARs were still emitting light, just very faint so you would only see it if the room was otherwise entirely dark. I am sure this is a new behaviour, and they were not having any current initially. Question: Is this an "aging" of the relays, is it something to worry about (safety etc.)? Like, should I change the switch, or this harmless or expected behaviour.
The photo shows the situation with relatively long exposure time (the blue LEDs are from a separately connected Wifi router, so are irrelevant to the situation).