Help! I can't play online anymore!

I don’t know what to do. Every match I play now ends up disconnecting for some unknown reason. Usually, everything is smooth and perfect until the disconnect occurs. Here’s my setup:

Router:
Netgear R6230-100NAS (brand new router)
5 GHz network (but issue also occurs on 2.4 GHz)
Firmware is up to date
NAT is open

The router is a mere 15 feet away from the Xbox (behind 2 walls). I cannot use a wired connection unfortunately due to the layout.

I’ve tried manually changing the DNS and making sure the wireless channel is set to “auto” but it makes no difference.

When I run the detailed network statistics from the Xbox settings, it looks like this:

Download speed: 47.39 Mbps
Upload speed: 5.82 Mbps
Packet loss: 0%
MTU: 1480
Latency: 33 ms
Wireless strength: 82%

Any ideas on what I can try next? I really want to get some games in! Web browsing and streaming video seem fine.