Disklavier

I am using wireless connection - possibly that is difference since you are using Ethernet cable. 

When in finder, can you select Go option in menu bar across top of Mac screen?  Can you select Connect to Server?
If so, do you see dialog box, with first text box highlighted with Service Address?

Select browse button to see if any servers show up.  Select your piano network name and you should see the various files used by DKV Browser.