[SOLVED] Can't connect via VNC or install JRiver

[agent_kith]

VNC does also work if I use the IP-nr:1 (largos:1 does not work) and the password Password1.

Whether "largos" works depends very much on your DNS/DHCP setup. Your DHCP server has to tell the DNS server that this IP has this domain name, and update the DNS with the new IP everytime it changes. Unfortunately most homes are not setup to work this way (unlike a office/enterprise environment), e.g. most home routers don't have a DNS built in.

However, there is another system called Bonjour or Avahi that will work around this - try the name "largos.local" instead and see if it works.

I can now play music from Jriver to my headphone DAC, Pre Box S2 Digital (a very competent small DAC), I have tested up to DSD128 files and everything works great.

Thanks you very much for the help. 
Keep this great job up 

Noice. Happy listening. Do try other players as well and compare then against JRiver. Common sense you will tell you all music players sound the same, your other senses might just beg to differ .