Strange problem after upgrading firmware on RT-AC87U and RT-AC68U

[jevel]

I have a strange problem with my setup after upgrading to the newer firmwares for my routers running as a pair where the RT-AC87U is the main router and my RT-AC68U is running as a media bridge. I have been stuck on older firmware where this works as expected, but due to the 5 GHz shutting down on the RT-AC87U I really need the newer firmware.

I have posted about this earlier, but got tired of the trouble and just flashed back to the older, working firmware. As the problem with the 5 GHz started again recently, I decided to give it another shot, but still I have these issues.

On the media bridge I have a Synology DS184 NAS directly connected by cable, and from time to time with no apparent pattern, I will be able to access the NAS when running on the latest official firmware, but the speed is terrible, and for no reason it just stops responding. On the older firmware the connection is rock solid reaching close to 70 MB/s on peak between an AC client connected to the RT-AC87U and the NAS.

I have reset both devices to factory defaults, both before flashing the new FW and then again after the flash. Several times. When I look at the client page of the RT-AC87, most of the time I will see the NAS listed, and from time to time I will also see the RT-AC68 with its own entry. But if I look at the "Wireless log" on the RT-AC87, I find something that I do not understand:

SSID: "Something (5 GHz)"
RSSI: 0 dBm SNR: 77 dB noise: -43 dBm Channel: 104/80
BSSID: 38:2C:4A:XX:XX:XX Supported Rates: [ 6(b) 9 12(b) 18 24(b) 36 48 54 ]

Mode : AP Only

Stations List
----------------------------------------
MAC Associated Authorized RSSI Tx rate Rx rate Connect Time
D8:50:E6:XX:XX:XX Yes Yes -50dBm 1170M 7M 00:32:13
00:11:32:XX:XX:XX Yes Yes -46dBm 1170M 1300M 00:32:11
54:A0:50:XX:XX:XX Yes Yes -69dBm 7M 7M 00:31:51
D8:50:E6:XX:XX:XX Yes Yes -50dBm 1170M 1300M 00:28:55
10:40:F3:XX:XX:XX Yes Yes -61dBm 360M 450M 00:19:46
B4:AE:2B:XX:XX:XX Yes Yes -58dBm 195M 468M 00:09:59

I notice that both my RT-AC68 and the Synology NAS lists as wireless clients. Do anyone know if this is to be expected, or am I seeing something that could possibly be a part of my problem here? I also have a repeater (RP-AC52) on my 2.4 GHz, and this does not show up in the same way.

Any ideas and / or help would be appreciated.

-KJ

 

[jevel]

Update:

It seems that also the RP-AC52 has trouble keeping a stable connection to my devices connected to its wireless. I have a couple of Sonos players and a couple of WiFi enabled babycams on the 2.4 GHz, and from time to time I will have trouble accessing the cameras or playing music on the Sonos.

I am also having a hard time using my Logitech Harmony Remote from my mobile devices.

This is very frustrating; I have the choice between a usable network that is unstable on the 5 GHz, or a stable network that is unusable for anything but internet.

-KJ