I promised to reply back if I had an happy ending!
And I did.
As I was suspecting, and the second time actually but I just didn't remember the first time, this TP-Link TL-PS110P network print server was the issue.
All I did is to unplug it from the network and 15 minutes later or so, the tuner came back by itself and remained available since.
Now, for the ones who are still suspecting a network IP conflict, no it wasn't because both had a different static ip mapped. And the print server was set to obtain an IP from the DHCP like all the other devices on my network.
This print server always caused strange things on my network but nothing showed in logs so it remained a mystery.
Thank you!