Sony HAP-Z1ES + MacBookPro


Love my HAP-Z1ES.  Used it to feed analog into my pre-amp; now using its digital USB output to feed my Devialet 200.  Truly happy with it.
Alas: this week, with my latest MacBookPro software upgrade (MacOS 11.3.1, an update to Big Sur) I can no longer transfer files (using the HAP Music Transfer app) from the laptop to the Sony.  I get error messages, either "Some files are failed in transferring. Please check the transferred file list." or "Transfer cannot start because the device has not been ready for it."  (I've never gotten either of these before.) 

I pinged Sony via Twitter but don't really expect an answer.

Everything else (playing existing files; using the HAP app on my phone as a remote) works fine.

Thanks in advance for any Audiogoner who has advice, diagnostics, workaround.
Ag insider logo xs@2xhrodman
Why does Apple make things so difficult in 2021?  You would think they would be more compatible with Windows operating computers.  BTW, the Sony runs on. Lynxes operating system. 
Thank you, all.  Have been corresponding with Sony support.  I might try drag-and-drop, though does that mean that Gracenote rather than yours truly supplies the artwork and metadata? 

For whatever reasons I'm seeing this as a Sony problem, not an Apple problem — perhaps because I've been struggling with an HP printer that always seems one or two versions behind the latest MacOS update ;)

Regardless: I've been listening to wonderful music on a good rig, and that's made all the difference during the pandemic.  Don't want to lose sight of that.
Continuing thanks,
   Howard.
With my Windows based computer, I never have any problems in getting the files onto my HAP hard drive.  I have moved  up to 300GB at one time with no problems. The Sony transfer software has nothing to do with Grace Notes, that is already on the HAP hard drive.  It really isn’t a Sony problem, it’s Apples. 
Wondering if you were able to drag and drop?  I just discovered that my Big Sur Mac won't connect to the HAP-Z1ES even though I can see it on the network.  The connection just fails when I try.  Likewise the Transfer software sees the Sony, but won't explore the drive or auto transfer.   
Very frustrating.