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
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.  
Haven't tried drag-and-drop yet; will report back when I do.  Thanks, kent_monkey!
My issue is that while I can see the HAP-Z1ES on my network, it will no longer connect.  No more drag&drop for me either.  I fear that this is linked to the Mac OS update.  
I can't drag-and-drop either.  While the HAP-Z1ES shows up on my network, it won't connect in any meaningful way. 

My wife's laptop runs MacOS Catalina and both HAP Music Transfer and drag-and-drop work fine.

Unless there's something I'm not seeing, Sony has yet to update their software to take the Big Sur changes into account. 

It remains to be seen whether they will.
I am sure Sony won't update the HAP software.  It has been discontinued for years and the amount of Mac users are probably a lot less than the Windows users.