In two out of three I have now - after several months, with less frequent use - a "half loose connection" behind the counter. I mean, you turned on the thing and then get for your listening pleasure the switch bright light to dim light. In dim light may be the machine shake like a Urwaldaffe or around manipulate the switch to get light bearable. Simply switch to the correct position jiggle where he thinks to want to leave power! Quite simply actually!
Apart from the lamp makes a very strong impression, but is apparently a blender. Or more specifically, a twilight, lol.
Conclusion for me: in the future I can save those "bargain" and only buy proven lamps. THE specialist forum for LED lamps is the way the candlepower Forum (English).