I have an Echo Mini, and I have come to really enjoy using it, both as a DAP and a usb DAC. I will say, the software isn't great. For example, whenever I add new files to the SD card, "favorites" are just wiped out, rendering the feature basically useless. Sorting is weirdly inconsistent. These are things that could be fixed with firmware updates,
I don't get why the firmware is closed source. Don't they have much more to gain by opening it and allowing enthusiasts to help improve it? What is the benefit of keeping the source secret?