Man that sucks mine have been running strong for over a year on 2 different x5s!!
Id give them a call the are very helpfull and sure they will make things right..
The plastic cylinder thing is anti flicker no error device.. I just tuck it back in the tub away from the light..
Maybe defective? Maybe too close to the aluminum heat sink of the led? I tuck it back as far as i can inside..
You might try without it or there is another set of wires in there i didnt need, you may need to connect those..
Looks like there is install site on back of box.. Www.weisslicht.com

Sorry! Dont kill the messenger! :p