Disconnections and poor sound quality

I ordered the Bluetooth receiver to connect my MacBook to my system. The straight line between the two devices is about 3 meters.
To set up it can be said that it is quick and easy, is also well described in the manual. For the quality of the supplied cable, I can not say anything (they have not used), only that they're right, "cheap" worked and were not very long. Since you should order a longer if necessary equal.

The connection was now so what then noticed was the poor sound quality. Whether this is now on the Bluetooth connection or the receiver, I do not know; but the tone sounded like a bad mp3.
Before I could listen to this in more detail, after 10 seconds, the connection was broken and I had to reconnect. After a few seconds the signal broke off again and did so after every new Connect.
The problem did not resolve itself, not with restart of the receiver and also not with reducing the distance and so went the Bluetooth receiver back.