Multiple NAT issue with Roon ARC

[Geoff_Coupe]

I see that you are using a 5G modem/router. It’s very likely that your ISP (who are they?) is using CGNAT and it is this that is causing the Multiple NAT error.

You need to talk to your ISP. See this post for more info and your options:

ARC: router_external_ip":"100.64 to 127.x.x" read this

I’ve noticed an increasing number of posts with this issue and the numbers are growing. Time I wrote this up as it should be a quick diagnosis. First, the problem: In Settings → Roon ARC if your diagnostics show: router_external_ip":"100.YY.x.x" where YY is a number between 64 and 127 and x.x is numbers. Then, if just underneath that, you see: "status":"status":MultipleNatFound There is an almost 100% chance your ISP is using Carrier Grade Network Address Translation (CGNAT). This is what…