Clearly your experience is not typical, and signifies that something is not right. I highly doubt that the USB cable is at fault (although a good cable can help get the most from a component).
I have owned the Zenith Mk3 for almost two years and have never had any issues with its sound quality. I have had some software related issues that were quickly resolved by their service tech (remotely, I should add).
It would be worthwhile contacting them to ask for their take on this before you give up on it. It's not out of the question that your unit has a problem that explains the poor SQ.
I have owned the Zenith Mk3 for almost two years and have never had any issues with its sound quality. I have had some software related issues that were quickly resolved by their service tech (remotely, I should add).
It would be worthwhile contacting them to ask for their take on this before you give up on it. It's not out of the question that your unit has a problem that explains the poor SQ.