I think it’s the sampling rate, dropped bits, or elimination of noise on the USB. PCM uses packets to wrap up and send information. If it runs out of time, it drops bits. The cost is resolution. Computers are getting better and better at this. It’s why I went to DSD back in the day.
Full disclosure - I’m an analog guy. I do use a PC for my digital (the horror) but I do not stream. Everything I listen to I have spent the past 25 years recording and cataloging myself from analog sources. For how I use it, it’s fine for me. Say what you want to say about PC/Mac as a source, I don’t have enough years left on this planet to redo that work. You didn’t say if you were streaming or playing from your drive. If you’re going to consider a streamer and you have cataloged your songs, I would look very hard at the interface and how it could hold onto that information.
Regardless, this sounds like a good problem to have. Congrats and enjoy.