Strong series differences ... stay away!

That is why I have just purchased as a system for my sister a week ago. (PID: SN017)
This is characterized by a loud hum and buzzing when just is not a signal to the speakers.

My girlfriend has the same time ordered these boxes. The first went straight back after the left speaker did not work and produced only crack.
When then came the exchange of product, there was the same mistake on the right speaker.
The boxes were not tested with other audio sources to the phenomenon to be verified.

I have the old and the new device open times and am almost fell off my chair.

The reason for the really poor quality of supposedly identical article was the fact that in the new series just once a few components were omitted!

The old version had two capacitors with (presumably) diode front.
In the new version was simply a capacitor omitted, the rest also dimensioned somewhat smaller and the diodes simply bridged by wire !!!

I also have a picture of this product uploaded to my execution underpin visually.