Wi-Fi 5GHz issue with Nexus-6P and Asus RT-AC87U router

[EnF70]

This issue only happens after some time, I haven't been able to properly identify the right conditions but a few possible triggers could be:
- connecting to another Wi-Fi and then coming back to home Wi-Fi network
- after overnight doze, in the morning

Hardware:
Nexus-6P with 6.0.1, Asus RT-AC87U with latest original firmware or latest Asuswrt-Merlin firmware (latest before 31.12.2015)

Verification:
ping your Nexus-6P from the local network, if you see ping times of around 2 seconds then the issue is there.

admin@rt-ac87u:/tmp/home/root# ping nexus-6p
PING nexus-6p (192.168.10.105): 56 data bytes
64 bytes from 192.168.10.105: seq=0 ttl=64 time=2.917 ms
64 bytes from 192.168.10.105: seq=1 ttl=64 time=1083.146 ms
64 bytes from 192.168.10.105: seq=2 ttl=64 time=83.068 ms
64 bytes from 192.168.10.105: seq=3 ttl=64 time=2098.707 ms
64 bytes from 192.168.10.105: seq=4 ttl=64 time=1098.448 ms
64 bytes from 192.168.10.105: seq=5 ttl=64 time=98.510 ms
64 bytes from 192.168.10.105: seq=6 ttl=64 time=945.520 ms
64 bytes from 192.168.10.105: seq=7 ttl=64 time=104.417 ms
64 bytes from 192.168.10.105: seq=8 ttl=64 time=113.390 ms
64 bytes from 192.168.10.105: seq=9 ttl=64 time=3.880 ms
64 bytes from 192.168.10.105: seq=10 ttl=64 time=41.111 ms
64 bytes from 192.168.10.105: seq=11 ttl=64 time=2083.710 ms
64 bytes from 192.168.10.105: seq=12 ttl=64 time=1083.688 ms
64 bytes from 192.168.10.105: seq=13 ttl=64 time=83.582 ms
64 bytes from 192.168.10.105: seq=14 ttl=64 time=2155.097 ms
64 bytes from 192.168.10.105: seq=15 ttl=64 time=1155.053 ms
64 bytes from 192.168.10.105: seq=16 ttl=64 time=154.946 ms
64 bytes from 192.168.10.105: seq=17 ttl=64 time=1921.035 ms
64 bytes from 192.168.10.105: seq=18 ttl=64 time=920.965 ms
64 bytes from 192.168.10.105: seq=19 ttl=64 time=3.532 ms
64 bytes from 192.168.10.105: seq=20 ttl=64 time=1991.599 ms
64 bytes from 192.168.10.105: seq=21 ttl=64 time=991.523 ms
64 bytes from 192.168.10.105: seq=22 ttl=64 time=3.394 ms
64 bytes from 192.168.10.105: seq=23 ttl=64 time=2063.511 ms
64 bytes from 192.168.10.105: seq=24 ttl=64 time=1063.289 ms
64 bytes from 192.168.10.105: seq=25 ttl=64 time=63.159 ms
^C
--- nexus-6p ping statistics ---
26 packets transmitted, 26 packets received, 0% packet loss
round-trip min/avg/max = 2.917/823.507/2155.097 ms

Testing:
1) Running OOKLA speedtest at http://www.speedtest.net shows no degradation in speed (compared to 2.4Ghz or 5Ghz before the issue)
What's more, the ping during the OOKLA speedtest shows a very stable 3ms for the duration of the test.

2) Streaming video over Plex (local network), Netflix (from Internet), streaming a movie from a local Samba/CIFS share is fine.
Same thing, ping is stable and low (around 3ms) while Nexus Wi-Fi is busy streaming content.

3) Streaming LIVE TV from a local Enigma2 satellite receiver is NOT stable.
The high ping latency breaks the streaming and the video is jerky, stops frequently and shows signs of degradation (low fps and image decompressions artefacts).
The ping varies a lot during this type of streaming and it shows response times of 2 seconds similar to the times shown above.
The type of streaming is RTP over HTTP from a Live TV source (the normal Enigma2 streaming). My sat receiver is a Vu+ Duo2.
I have tried both HD and SD TV channels with normal streaming (not transcoding) as this requires a low latency network to stream properly.
I also have tried various video players on the Nexus-6P like BSPlayer (both software and HWacc), MX Player and the internal video player of the VU+ client.

Notes:
1) The issue doesn't happen on 2.4Ghz (same router) I have tested it for a week, everything stays stable on 2.4GHz
Ping times over 2.4GHz vary between 3ms and 300ms but nowhere near the 2 seconds observed on 5GHz
2) The same LIVE TV streaming (same source, same players used) works perfectly over 2.4GHz (same network, same router, same everything) and on 5Ghz before the issue appears (high ping latency).
3) Rebooting the Nexus-6P changes nothing, after reboot the 5GHz high ping issue is still there
4) Rebooting the Asus RT-AC87U router solves the issue, everything works fine until the issue surfaces again

Before blaming the router, I have other 5Ghz Wi-Fi devices on the network (Samsung S4, HTC One M7, MacBookPro, iPad Air, Samsung TabS) and they all work fine, no issues streaming Live TV on them from the same source.

Posted this in the XDA-Developers forums as well here:
http://forum.xda-developers.com/nexus-6p/help/wi-fi-5ghz-issue-asus-rt-ac87u-router-t3285533

 

[sfx2000]

Before blaming the router, I have other 5Ghz Wi-Fi devices on the network (Samsung S4, HTC One M7, MacBookPro, iPad Air, Samsung TabS) and they all work fine, no issues streaming Live TV on them from the same source.

I don't know if I would blame the router on this issue - if possible, can you test on a different 11ac Router model and see if the problem continues?

At first glance, I'm thinking something with power management and the sleep timeline in Android, and perhaps something specific to the Huawei configuration - or something specific to that application (Enigma2) - weird...

 

[joegreat]

Hardware:
Nexus-6P with 6.0.1, Asus RT-AC87U with latest original firmware or latest Asuswrt-Merlin firmware (latest before 31.12.2015)
Before blaming the router, I have other 5Ghz Wi-Fi devices on the network (Samsung S4, HTC One M7, MacBookPro, iPad Air, Samsung TabS) and they all work fine, no issues streaming Live TV on them from the same source.

I would bet that this is related to the know issue with Asus Beamforming - disable it in the Wireless/Professional tab and try again...
Many SmartPhones/Tablets seems to have issues with Beamforming!

 

[kdan3388]

my router would work for a day or 2 and then start lagging bad, doesn't matter beam forming off or on

PS: all my devices are iOS

 

[EnF70]

I would bet that this is related to the know issue with Asus Beamforming - disable it in the Wireless/Professional tab and try again...
Many SmartPhones/Tablets seems to have issues with Beamforming!

I have all beamforming options disabled.
At the moment I am using 2.4GHz with Nexus-6P and it's stable and fine but still testing 5GHz.
I don't have any issues with my other devices on 5GHz.

 

[NolanW]

There's known issues with the antenna drivers for this router, including excessive battery drain.

Also, there are a few WiFi related issues on the android bug tracker. See if maybe one of those applies to you.

 

[bryantjopplin]

There's known issues with the antenna drivers for this router, including excessive battery drain.

Also, there are a few WiFi related issues on the android bug tracker. See if maybe one of those applies to you.

Router battery drain? If you mean the nexus 6p has driver issues and battery drain then yes. This is a know problem. The nexus 6 also has a problem when upgraded to marshmallow. My n6 gets around the issue but using the new 6.0+ kernel with 5.1 wifi drivers. Also I am/was having issues with the channels causing issues in the 5ghz only band. Change your channel to anything below the 149 seems to help.

Sent from my Nexus 6 using Tapatalk

 

[bryantjopplin]

I have all beamforming options disabled.
At the moment I am using 2.4GHz with Nexus-6P and it's stable and fine but still testing 5GHz.
I don't have any issues with my other devices on 5GHz.

With good channel

With bad channel.

Sent from my Nexus 6 using Tapatalk

 

[NolanW]

Router battery drain? If you mean the nexus 6p has driver issues and battery drain then yes. This is a know problem. The nexus 6 also has a problem when upgraded to marshmallow. My n6 gets around the issue but using the new 6.0+ kernel with 5.1 wifi drivers. Also I am/was having issues with the channels causing issues in the 5ghz only band. Change your channel to anything below the 149 seems to help.

Sent from my Nexus 6 using Tapatalk

No, I mean the WiFi antenna firmware on the router itself is causing a battery drain on all devices on the 5ghz band.

 

[bryantjopplin]

No, I mean the WiFi antenna firmware on the router itself is causing a battery drain on all devices on the 5ghz band.

OK makes more sense that way lol

Sent from my Nexus 6 using Tapatalk

 

[Savaloco]

I feel enf70's pain and find myself in the same situation. It seemed our 87u would constantly cause both of our household's N6p devices to the 2.4 band. I initially blamed the router and have contacted ASUS to RMA it but the more I dig the more it seems the N6P or the combo of the 87u and phones are to blame as I have found my Son's Samsung is constantly conected to 5GHz. This said he does occasionally complain if poor performance but nit nearly as frequently as what has been experienced on the two N6p devices.
I have installed the latest drivers, reset the router nultiple tumes, and have made a number of other adjustments like those suggested here to no avail.
Unlike enf70 our 2.4 band has also been somewhat flaky causing data overruns as my N6P swithes to mobile data to serve my netflix viewing needs.

Frustrating!

 

[EnF70]

Update:
Just discovered that a MacBook Pro (Retina, 15-inch, Late 2013) using 802.11 ac is also affected on the 5GHz WiFi.
Very similar to the Nexus 6P, ping and low-latency video streaming issues.
Another MacBook Pro (Retina, 15-inch, Early 2013) which only supports 802.11 a/b/g/n is not affected on the 5GHz.
No issues for any device on the 2.4GHz.