My sons live with their mum and she has a Deco P9 system with one pod connected to the cable modem covering downstairs and another for upstairs with powerline backhaul.

The system was oly bought in the 4 months and has worked well.  Wifi signal is great all over the house and the backhaul has a strong signal.

However they are now telling me that this week when son 1 is playing on his Xbox Series X and son 2 switches on his Windows 11 PC the network latency massively spikes and the Xbox Series X is affected to the point of online games failing.  Switch the PC off and the latency drops.  Speeds appear fine though.

Anyone got any ideas?  Things I can get checked or looked at, especially on the PC.  I have good IT experience but not with the newer Windows OS versions.  I'm happy to advise them on what to do.

I have a PX50 system and may get them to test things here.  If it were my system I'd be changing the QOS to prioritse the Xbox to test and look at what the PC is doing but I'm not sure what possible on the P9 system via the app. I'd also do a network scan to check everything is happy.

Any help appreciated.

Radar