We've had two iPhones do this where the iPhone disconnects whenever the screen is turned off (every time) even when it is within close range of the router. In both cases it came after an iOS update.
I was able to eliminate the issue with a simple Reset Network Settings on one phone, and on...
It's been a while since I've done that on my AC68U, but I recall just resetting to factory defaults, and then configuring manually. I didn't do a JFFS format.
Again, the OP is trying to tackle two issues:
1 - disconnects on Ethernet, and
2 - slowdowns on Wifi
Smart Connect gives the potential for both a dropout (momentary), and slowdown in wifi.
SmartConnect will not help if this is what he wants out of his Wifi.
Aren’t the disconnects happening on a PC connected by Ethernet and not wifi?
And for 5Ghz, why would you suggest 160mhz auto if it’s going to push into a DFS channel that could get knocked off? 20/40/80 avoids that possibility.
And Smart control gives you no control. You could land on 2.4ghz...
Using the Merlin Firmware, the QOS tab has the ability to use Speedtest from within.
You can look up what the Merlin Firmware is, but basically it is a customized Firmware based off of the Asus Firmware. More bells and whistles, if you want them, but generally the same look and feel as the Asus FW.
I’m also back on 46E9 with my N66U, 24+ days of uptime.
Prior to this, 48E7 and 49E4 would reboot after 5 to 7 days, with watchdog in the error logs.
I haven’t seen this code in 46E9 ever.