LED Dimmer with weaknesses

My first very positive assessment, I must unfortunately revise downwards:
The dimmer is specifically advised by Philips. Works in principle first times very good,
I can turn down my Philips NV-LED 7W each to about 10-15% of full light output.
Without hum and (initially) without flickering.

Unfortunately, I realized in the meantime that after about 2 hours of operating time to flicker start the LEDs.
You do not go out, but be brighter or darker at certain intervals. It's frustrating!

Replacing the older transformers to a special LED transformer brought no change.

Thus it is either the LEDs themselves or just the dimmer or the combination.

Pity!

Update: I had had enough, and have thrown out those expressly designated for my LED dimmer and replace it with another product:
PSC = 1
Costs less than half as the Busch-Jaeger, matches the Busch-Jaeger series (central disc can still be used) and one can without the hassle Geflackere dim!