Wireless troubleshooting an iPad on UNIFI wifi

jbeez · June 24, 2022, 2:09pm

I’m having a reliability issue with this iPad Pro unit and I’m trying to determine if its the network or the iPad itself. Let me lay out the network:

PfSense 2.6.0-Release on a Supermicro SYS-E302-9D(probably not relevant)
Unifi controller 7.1.66 on a debian VM on the lan
FW → US-8-150W Switch → UAP-AC-SHD direct on this switch(2 ports bonded)
two SFP connections to a Edgeswitch 24 lite → cat6 to a UAP-AC-PRO.

Focusing on 5ghz, using 80 channel width setting. Airway is clear on the RF scan for both.

The issue, iPad stutters bad trying to game on wifi. One glaring example, iPad running playstation remoteplay to a PS5 unit. PS5 is hardwired in the edgeswitch lite, I can lock the iPad to either access point and it just is so bad its unplayable. I take the iPad off wifi and use its cellular data on tmobile and it performs flawlessly. Also I have a usb-c to ethernet adapter, and that works perfectly fine.

Signal strength on the iPad is 99%, its about 10ft with direct line of site to the SHD at the time. It goes through some walls for the Pro but still a great signal if i lock to that. Connects to the SHD at 866mbps on 2x2 MIMO.

So far the extent of my diagnostics has been ping, the ping to the iPad, and infact I’ve noticed… anything using MIMO seems to bounce around wildly. I have a homepod sitting right near where the iPad was setup, and the latency will jump around from 2.x ms to 100ms+

The ipad was doing similar. Not sure if that’s even relevant. But I do know when I pick something connected to wifi with 1x1 mimo like my ecobee thermostat which is also sitting right next to the homepod on the wall, the pings were extremely consistent under 4ms for all of them.

There has been no packet loss, but I haven’t attempted to ping during it being terrible.

I’m looking for suggestions on what data I should be looking at to troubleshoot this deeper, and maybe how to get that data. Maybe I need an app on the ipad that can get something, it seems limited to me on the ipad side for what diagnostics I gather there.

If I were just looking at this in the Unifi web portal, I’d say everything was fine, but in practice its performing terribly. Any feedback appreciated, if you need additional information I can gather. I’m going to list some of my unifi settings as well that are frequently asked for.

Band steering: Off
SHD: VHT80 Channel 36 Transmit power: Auto(26 dBm)
Pro: VHT80 Chan 100(DFS) Transmit power: Auto(25 dBm)

Wireless Mesh: off
Auto Optimization: off

TIA

jeff3820 · June 25, 2022, 11:07pm

Just curious…is this a first gen iPad Pro? I have one of those and the WiFi performance is erratic. I had a second that did the same thing so I traded it in.

Something you might try on the iPad…reset the network settings. Settings, General, scroll down to the bottom and choose reset, reset network settings. You will have to enter all your WiFi passwords again. This helped quite a bit on my M1 iPad Pro. Checking now to see if the first gen iPad Pro improves.

What firmware versions are you running on your access points?

jbeez · June 27, 2022, 4:33am

Thanks for the response Jeff.

6.0.21 on the AP firmware. It’s a 12.9” iPad Pro 5th Generation, purchased last July actually.

Reset the network settings today, it didn’t help.

What I did try finally, is in the ps remote app theres a setting for HDR, I turned it off and so far so good.

Today a friend of mine with the same iPad stopped by and tested doing remote play from his ipad back to his house using my wifi, and it worked flawlessly.

I also ran some diagnostics on my FW and AP’s by way of packet captures to see if the ps app was maybe routing out and back in but it wasn’t the case, everything was direct. 172.22.1.188 talking directly to 172.22.1.45 with UDP.

At this point I think its a bug in that app with HDR setting. I think the wifi was just good enough for it to try doing it, but it was failing, When it connects over cellular it knows to not even try it. When it connects over a slower link it doens’t try in(was set to automatic). At this point I think the network and equipment is fine.

edit: I need to more thoroughly test this, its really my going theory right now, need more time!

jbeez · July 3, 2022, 5:21pm

I’ve done some additional troubleshooting and I still don’t have an answer but have a weird work around/band aid.

Added a Unifi Mesh AP that does WiFi 6 to broadcast the SSIDs in place of the SHD. No improvement.

Added a 2.4Ghz only SSID with a different name, extreme improvement. This works very well despite the negotiated speeds being about 1/10th those of the 5GHz network. I also tried enabling 5GHz on this SSID just to see if there was something corrupt with my other SSID configuration, but the issue persisted.

So Ethernet or 2.4Ghz and this performs flawlessly. When I try to run it on the 5GHz SSID or dual SSID it’s extremely choppy. Guessing the iPad has an issue with 5GHz networks. Not really sure how to troubleshoot that at a more granular level. The connection looks great on 5GHz, just doesn’t work well in practice.