Durability very limited

I bought two of these input switches and the computer
connected. At first they worked wonderfully, but already
after about six months they are completely and ausgenudelt
produce dropouts without end. By tapping on the enclosure
let a and turn off. Meanwhile, even by
Vibrations at the desk.

Normally the switch had about 3-5 shifts on
To cope day. Since it's sad when half for a
Year are already totally worn out.

On top of the already mentioned problem with the common
Dimensions.

Although the housing is high per se, is the inner workings
just inferior electrical scrap.