THe Zynth doesn’t need Ethernet to start in normal operation so that isn’t the cause of your blinking as you describe it. It more likely that you haven’t configured the device via webconf, but of course to do that you have to connect to a browser via … an internet connection.
Sadly the default wifi connection is off so the zynth by itself is not going to connect to any wifi it does detect ( their are pi’s without wifi in the early days of the zynth so it wasn’t an option.
The file you are looking for is
which is a shell script that sets the environmental variables. . . So be careful with syntax like ='s and #'s and such like
The file is mentioned here ( Zynthian GUI start up walkthrou' - ZynthianWiki ) which might explain some of the details.
You also have the wpa_supplicant.conf file for the wifi details.
You have discovered one of the zynth gotcha’s so congratulations! This doesn’t releave you of your duties (press on the moncle’d icon if this makes no sense) … but we obviously need a working zynth before we can admire the contribution !
Obviously this relies on you getting access so if if doesn’t work as you would like get back on and complain here vociferously !
The kit will need setting
and the Audio card and display
export SOUNDCARD_NAME=“Dummy Device”
export DISPLAY_NAME=“Generic HDMI Display”
That should get it going, or a little bit further down the road. I’ve not tried doing this ( or if I did it was back when the earth cooled …) so I could well have forgotten something critical but if it gets as far as the gui you can do turn on and off stuff like the wifi via the admin function, and once you can do that you can start a hot spot to get to the webconf via wifi…
Tell us how it goes.