VLC Player jerky at MKVs - not recommended Service

I bought the device as a multimedia center for the living room. Here it should play for a video, music and pictures from a NAS and enable Internet access. Everything is displayed on TV or projector.
First the positive:
- The device looks very good
- It is absolutely noiseless
- The Insallation doing great
- The connection of a wireless multimedia keyboard was not a problem
- Videos (AVI), music, pictures no problem
Now the negatives:
- The computer is less powerful than expected after the data because
- The memory of the GraKa with genutz is - sharing
- Both the included 32 bit VLC Player as well as the 64bit player from the network can not play smoothly MKVs
every 5 seconds a hanger
- 3D MKVs not go because jerky nothing more, is there anything
For the computer for me was not usable.
But that was not the end ...
I have exercised my right to object and returned the computer. Until then, the service of the dealer was ok. Returning at his own expense will be refunded. The shipping cost to me not. But the computer came back with the note - the dealer is warped and do not want subsequent delivery. I had made the "mistake" and put the address of the enclosed service waybill. And now began the great communication with Mega Computerworld. I asked MCW me to reimburse the cost of transport and to call with the correct address. The right place was in the email invoice. MCW refused or refuses to this day to recover the cost, because they had not done in the consignment note the package and it does not exist the. The mission of the scanned bill did not help. The bill was further negated. After several mails I've given up and the additional postage borne itself. A (eventual) concessions or even understanding allowed the communication in the mails miss. As long as the machine is running fine, but ...
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