Qubino Flush 2 Relais misbehaves once every x times

UPDATE 2: The Qubino is often not working when put in the wall, but works perfectly when it’s hanging out from the wall. I think the built quality is too poor and stresses coming from stiff wires cause malfunction.
I always put most of the wires into the wall, then the Qubino, and than the be-stable switch. I found out by lots of trial and error that it’s better to first put in the qubino, with the flat back against the back of the hole in the wall, Then put the wires in between the Qubino and the be-stable switch. Now it is working again, and hopefully never stops.
Do others have the same problems? And how is that with Fibaro’s?