Almost since I started streaming in 2007, I’ve used approximately the same network layout. Nowadays it contains a ISP-router and a Netgear GS108T switch. NAS (Synology with 2x HDD), WAP (Linksys), DS and network hub connecting the rest of the house are connected to the switch. Everything is placed in a connecting room to the living room housing the LINN stuff resulting in a long Cat run between switch and NAS.

Now I’m considering tidying up the network, adding another GS108T switch only connected to the NAS and DS. Thus “isolating” the music part of the network. Ultimately this part of the network would be placed near the LINN stuff with 2,5m BJC Cat 6a between NAS/DS and switch. This arrangement demands a “silent” NAS and since I’m not capable of building a Linnofil Super NAS nor have the means to buy a Melco NZ1, I wonder if anyone here do know of any other “silent” NAS (SSD) that is worth considering?

Qnap do a range of "silent nas's" into which you could install SSDs. Simply then add Asset or similar as an app.

I have Synology DS218 and DS118 with WD Gold drives and they are unbearably noisy (fan noise, disk noise). I had to relegate them to a closet where they cant be heard. I also have a WD MyCloud EX2 with WD Red drives and it is pretty much silent (fans and disks).

I wouldn't recommend my Synology setups for your application.