the box pro MBA1

I bought this item which included the speaker, the microphone and stand. I can have no complaints about the stand or microphone but I do about the speaker and the repair service.

I used the speaker 2 or 3 times before it began emitting a strange hissing sound when idle. I checked other reviews of the product and many complained of the same problem. I then contacted customer service who requested that I return the product to be repaired. However, I had to pay for all delivery costs including packaging etc. It was then returned with a note saying that in fact, there was no problem and it was just 'normal background noise'. When I turned on the speaker, it emitted exactly the same sound as it did before it was supposedly 'repaired'.

My question is, why was I forced to pay for delivery costs for my product to be sent for it to not even be checked for issues? Once it arrived at Thomann, it was immediately repackaged and sent back. What a waste of everyone's time and money.