OPi Zero USB WiFi issue

Hi. I encountered problem, glimpsed through topics and didn't found anything similar so I am posting this one now. 

Had set up OrangePi Zero 256MB version with Domoticz and everything looked great. I have 2 internet connections, one is PON FTTH and the other one is VDSL. So I have 2 routers with RJ45 and 2 WiFi networks at home. One for my personal usage (ftth, locked router by ISP, static IP but no port forwarding) and the other one is for all home users (dynamic IP but full access to router options). I hooked up OPI using cat5e cable to my router and this connection is working perfectly reliable. I had XR819 hooked up to VDSL router as auxiliary connection (and connection to ESP8266-based sensors) but it wasn't great and despite showing connection it was stopping to respond through WiFi after some time. So I upgraded armbian to:  ARMBIAN 5.36 user-built Ubuntu 16.04.3 LTS 3.4.113-sun8i, disabled WLAN0, blacklisted XR819, and used TP-LINK TL-WN422G spare dongle instead.

Networks connected, IP provided: 192.168.3.7 192.168.1.43

Seems ok. Both adapters up and reports ok but after some time (several hours) I can't access domoticz page through auxiliary network (and sensors lose connection with domoticz as well). So at this moment it doesn't appear to be hardware related as the same problem occurred on old kernel with XR819 on-board WiFi, and newer kernel with atheros chip. Anyone have idea why this happens and how can I retain both RJ45 and WiFi connection reliably? Restarted OPi so log at this moment dmesg doesn't show anything particularly useful. I'll fill in some info tomorrow if it fails again (which I suspect it will). 

connection lost at 7:47 AM, dmesg doesn't really show any useful information regarding it. Interface through system looks still connected with:

Quote

wlx54e6fc86b1cb  IEEE 802.11bgn  ESSID:"XXXXXXX"
          Mode:Managed  Frequency:2.437 GHz  Access Point: 18:1E:78:AA:DB:67
          Bit Rate=26 Mb/s   Tx-Power=20 dBm
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=39/70  Signal level=-71 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:121  Invalid misc:551   Missed beacon:0

 

syslog:

 

Jan 22 07:47:55 sun8i rsyslogd-2007: action 'action 9' suspended, next retry is Mon Jan 22 07:49:25 2018 [v8.16.0 try http://www.rsyslog.com/e/2007 ]
Jan 22 07:47:55 sun8i dhclient[589]: DHCPACK of 192.168.1.43 from 192.168.1.1
Jan 22 07:47:55 sun8i NetworkManager[482]: <info>  [1516603675.5429]   address 192.168.1.43
Jan 22 07:47:55 sun8i NetworkManager[482]: <info>  [1516603675.5654]   plen 24 (255.255.255.0)
Jan 22 07:47:55 sun8i NetworkManager[482]: <info>  [1516603675.5657]   gateway 192.168.1.1
Jan 22 07:47:55 sun8i NetworkManager[482]: <info>  [1516603675.5658]   server identifier 192.168.1.1
Jan 22 07:47:55 sun8i NetworkManager[482]: <info>  [1516603675.5659]   lease time 86400
Jan 22 07:47:55 sun8i NetworkManager[482]: <info>  [1516603675.5661]   nameserver '192.168.1.1'
Jan 22 07:47:55 sun8i NetworkManager[482]: <info>  [1516603675.5662]   domain name 'home'
Jan 22 07:47:55 sun8i NetworkManager[482]: <info>  [1516603675.5694] dhcp4 (wlx54e6fc86b1cb): state changed bound -> bound
Jan 22 07:47:55 sun8i NetworkManager[482]: <error> [1516603675.5979] platform-linux: do-add-ip4-address[4: 192.168.1.43/24]: failure 17 (File exists)
Jan 22 07:47:55 sun8i NetworkManager[482]: <error> [1516603675.6185] platform-linux: do-add-ip4-route[4: 0.0.0.0/0 600]: failure 3 (No such process)
Jan 22 07:47:55 sun8i NetworkManager[482]: <warn>  [1516603675.6187] default-route: failed to add default route 0.0.0.0/0 via 192.168.1.1 dev 4 metric 600 mss 0 src user with effective metric 600
Jan 22 07:47:55 sun8i dhclient[589]: bound to 192.168.1.43 -- renewal in 32582 seconds.
Jan 22 07:47:55 sun8i dbus[477]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service'
Jan 22 07:47:55 sun8i systemd[1]: Starting Network Manager Script Dispatcher Service...
Jan 22 07:47:55 sun8i dbus[477]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
Jan 22 07:47:55 sun8i systemd[1]: Started Network Manager Script Dispatcher Service.
Jan 22 07:47:55 sun8i nm-dispatcher: req:1 'dhcp4-change' [wlx54e6fc86b1cb]: new request (1 scripts)
Jan 22 07:47:55 sun8i nm-dispatcher: req:1 'dhcp4-change' [wlx54e6fc86b1cb]: start running ordered scripts...