Hi fazee - nice to think I might have been able to help. On the other hand, maybe you just got lucky :-)
Based on the fact I did not install memory in my Aries Mini, playing locally stored files DOES require the hard drive be connected. I say that for the ALAC files from ripped CDs that I have stored on a 2TB Seagate hard drive. Don’t know about DSD files specifically, but can’t see any reason they should be different UNLESS your particular model comes with internal storage and you load the DSD files to it.
I have the Aries Mini AND connected hard drive powered up all the time. Would prefer not to (at least for the hard drive) but there isn’t any real power switch apart from pulling the plug. Powered up, it’s ready to go all the time. Occasionally I will disconnect the hard drive to add another ripped CD. It seemed like in the beginning it took a few minutes to rescan the library. Lately (there have been some software updates) it takes hardly any time at all for it to read the updated library.
Good luck with yours. Hope you enjoy music with it. It is almost the only thing I listen to these days. Realizing for me that can mean, ripped CDs, Tidal, Spotify, or Internet Radio. Lots of variety. Check out Paradise Radio if you have not. Good stuff. Reubent had posted about that one.
Ciao