I've already posted about my issue with a USB DAC not performing the way it should on my 2015 MBP. In fact, I have two DACs, from two different manufacturers that perform in every way they are supposed to on two other Mac computers ( a 2012 MBP, and a 2015 Macbook), but not on the 2015 MBP. This, regardless of the OSX being used. It has to be some kind of issue with the 2015 MBP. I have AppleCare through June of this year on the 2015 (which functions well in every other aspect that I use it for). I must have some recourse with AppleCare regarding the 2015 machine since it is obviously not working the way that it should when it comes to these two devices. What would be your advice about my situation? I should be able to use the 2015 for every function that I want it to be used for. I should not have to compromise by using some sort of workaround (using another Mac to fulfill this one function that this Mac will not perform). What do you think?