I'm not sure there is any data (other than anecdotes) to say RE: Shanling M0:Well if the issues are confined to the non-black units then I can certainly live with black. I also wonder if your replacement might have come from a later batch. Do the units have the serial number on the back of the unit and did the replacement come with more current firmware? It could give clues as to when the unit was produced. I had battery issues with my Sony A17 and Sony shipped me a newer unit rather than try to fix my old one. The newer unit had a noticeably better build quality and sound quality was better as well and has worked perfectly for 3 years now. The old one was produced in July 2014 but the replacement was produced April 2015.
- black units - with out issues
- non-black units - with issues
To really know you would need the numerator and denominator for sales and returns to understand the percentage of defects.
Only the company knows that.
Posts on audio forums may be hypothesis generating, but aren't capable of generating definitive statements.
Mike