So I tossed this DAC in a closet after I got bored of trying to make it work right and forgot about it for a year or so till earlier today when I found it while cleaning. My Nexus 5 has been retired and serves no purpose other than a security camera now. I now have a Samsung Galaxy S5 and an RCA Maven Pro tablet. The RCA Maven Pro is an 11.1inch 2-in-1 Android tablet with detachable keyboard for around $120. You'd assume it's horrible thanks to the brand and price but they managed to cut corners in all the right places it seems. Downsides are no GPS, 1GB of RAM, terrible cameras, and a horrible speaker. Other than that it has faithfully replaced my $1200 laptop with zero issues other than adjusting to ditching Windows.
Now back on track when I listen to music I'm either using an aux cord plugged into my work truck or bluetooth when using headphones or in my new car. When doing a side by side comparison bluetooth, to no surprise, shows no difference between my Maven and S5. However when using an aux cord the RCA doesn't put out as much bass and highs are... I guess not as clear? I think audiophiles are insane most of the time so it's hard for me to describe when I do notice a difference. Anyways I plugged the UCA202 into the RCA's USB port (no OTG here, it has a full size USB port) and plugged my Sony MDR-XB950BT headphones in to it with an aux cord (these headphones are 100% passive when wired, no bass boost or other enhancements) and sound quality is just as great as my S5, all bass and highs are restored. Just to further the test I plugged it into my S5 and did the same test with the same results. These are the same FLAC song files from the same network location that my Nexus 5 was playing a year ago.
The whole time the issue was something in my Nexus 5. What it was I don't know and sorry you guys I don't plan on investigating, I just wanted to inform everyone that the Behringer UCA202 is in fact a quality budget DAC since this thread is a top Google result for "Behringer UCA202 Android". If you have a cheap device that you want the audio to be on par with the high end phones this will do it, and for my original purpose of at the same time giving a bit of amplification for a weak head unit without distortion it does that decently too. To finish this off I am NOT an audiophile. Just a human with human hearing that likes songs with bass on car head units that weren't always designed for it (I glued a 80mm CPU fan to the back of the HU in my Jeep

) So take my finer details however you'd like.