PS5 Speed test

Hi all,

Have RBR50 and 2x RBS50s. Plugged into cable modem (Arriss something or other) in modem mode - I recently changed this to modem from router, via factory reset.

I have a 1gig contract from my UK ISP, Virgin Media, which is fine. We typically have about 35 devices connnected (a couple of NAS drives, 2 or 3 tv's, Sly Q TV/satellite boxes, PS4, PS5, a couple of wired PCs, a couple of laptops, Arlo security cameras, Ring doorbell, house burglar alarm, iPads aplenty..). I have wired as much a I realistically can of the static devices, with a couple of unmanaged switches, mostly running cat6/7 cables.

My query is particalry about the PS5 that is wired to the RBR50 with a cat7 cable, interested for any views/others with similar experience.

Before reset, we had double Nat, which I don't think was causing any particular issues, but for neatness (and I was bored and needed a little project to do), I retired this config to single nat everything onto Orbi. However, something I had noted was that the PS5 when wired to RBR50 only ever achieved 150-250mbps download on the built-in speed test, whereas, when plugged directly into the cable router it would achieve 850-950mbps. This was reproducible at will in back-to-back tests seconds apart.

It's obviously not that big a deal with the speeds being achieved and we have very low latency and 5pmbps upload, after Virgin upgraded local capacity recently having been identified as an issue during the pandemic.

But, to satisfy my idle curiosity, I'm wanting to work out why the PS5 gives such different results between the cable router and RBR50.

Thanks for reading this far..