The Osram transformers, the minimum load should be only 20 W yes. Led flickered but still.
Temporary solution was replacing a LED lamp against a normal 20W halogen spotlights. Would then be about 44 W have been.
So it went smoothly, but that was not indeed the intention. So new transformer was needed I bought Isolicht LED Universal Transformer 0-70W dimmable. This goes smoothly for 3 days with 3 X 6 W.
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