Hi,
I’m running a synology 1515+ with Roon for pure streaming of music, nothing else. There are numerous services running in the NAS, I wonder which of those can any of you Guru’s can help me suggesting exclude without problem? with Roon and PS Audio DAC in mind… 
PS The streamer is a PS Audio Bridge II DS
Thanks in advance
Juan
Personally, as none of them are using significant memory or CPU I’d just leave it as is.
Otherwise you risk turning off services that you may at some point in the future want to use and causing yourself an unnecessary headache when things don’t work as expected.
I could suggest a couple of services on that list that you could problay live without, but I don’t know your exact circumstances — for example how you normally access the Synology to store files on it. So I’d tread carefully, what may be an unnecessary service for one user could be crucial for another.
What I would suggest is making sure that your Synology isn’t open (by default) to the wider internet and that your router/firewall is only allowing access to the services / ports (on the NAS) you know you need — which should be a fairly small list to start or none at all if you never access your NAS from outside your local network.
Makes sense thanks! 
