Anyway, I have today connected my iPad Mini to my (bought as used from eBay) XR700's wlan0 then wlan0.1 (for 5GHz) pulling continuous YouTube videos running on each connection for some 30 minutes.
Each connection ran continuously. And successfully.
I am happy that 5GHz works on my XR700. This XR700 will be installed at a customer site. Netgear routers running DumaOS are not totally new to me. I flashed a XR500 last year with DDWRT.
Lastly, I donot want to test using cli script unless there is no other way for me to find out. I've done enough in DOS environment to experience the barriers of technical gap in dealing with customers. Needless to say I feel confident of my ability of testing & setting up routers and switches.
My earlier post (immediately above yours) was a contribution toward helping decipher the rather mysterious and flaky work-ability of 5GHz as raised by several posters, but not of my experience. And no more than that.
Wishing you a great New Day of the Lunar Year today (Feb 10th 2024). Cheers
I haven’t touched my xr700 for almost half a year now. I have been using a new Asus RT-AX88U router that is just as fast as the xr700 and same range but with AX and 2.5G port. Finally got a chance to dust out my xr700 to try the latest dd-wrt bins to see if there is any change from the last few comments.
I started out my xr700 in the Netgear Duma V1.01.1.20 with the serial port to Putty, and also observed the wifi signals on my Android tablet with WiFi Analyzer. I saw the 5GHz band on WiFi Analyzer but at very weak level. No 2.4GHz observed at all. But at least it showed that the 5GHz was not dead. Duma OS reported that both 2.4 and 5 were enabled. So this is all the same as before.
Then I upgraded from Duma to DD-WRT R52369 04-20-23 bin that I knew it worked. I made sure I decoupled the 2.4/5 smart connect function in Duma with separate SSID’s before converting to dd-wrt (made no difference). 2.4G came on normally as wlan0 with full power as observed in WiFi Analyzer, very stable. 60G was on configured as wlan1 but I have no receiver to check. But there was no 5G configured. All this behaved exactly as before.
Then I upgraded to the R53469 12-04-23 bin with no reset of the nvram. This bin was successful in the upgrade, unlike what I reported before that the bins from 5-23 to 09-23 just hung up and never completed. But the WiFi status is the same. 2.4G was perfectly good but no 5G detected.
Then I upgraded to the latest R55109 02-09-24 bin with nvram reset option on. This latest bin was also successful flashed. It has the same WiFi status with 2.4G good at wlan0, 60G on wlan1, but no 5G detected.
Looking at the boot logs from the serial port. First there were 3 bad blocks in the Macronix nand flash chip. They all located in MTD13 nvram partition for dd-wrt (same config partition in Netgear Duma). I read the NVRAM content, lots of lines of parameters. Seemed everything was there, over 1000 lines. 20065 bytes used and 111007 left. I am not sure the bad blocks made any difference as they were at the very beginning, middle and end of the partition from their addresses.
After nvram was reset, the boot log showed that the 2.4G went through SNR calculations to determine the optimal channel. Then I believe it was gonna do 5G initialization. It encountered:
nl80211 driver initialization fa[ 47.916904] export_store: invalid GPIO 459
gpio 459 has a problem
Then it moved on to complete other tasks as it never loaded 5G.
I am not sure if it is a hardware issue with a particular GPIO pin. Driver initialization failure in dd-wrt may or may not be a hardware issue. There was no such error under Duma boot and 5G actually was commanded with output power under Duma as shown earlier. Really unusual this all happened right after the Duma bin upgrade. I am really not convinced any hardware suddenly went bad so coincidentally after bin upgrade. Why is there no 2.4G on Duma but 2.4G is normal on dd-wrt? Why is there some 5G level on Duma but none on dd-wrt? I still have no answer.
This is all I found in this last exercise. Unit back in the box. Life has to move on.
Thanks for reading.
unless there is no other way for me to find out. I've done enough in DOS environment to experience the barriers of technical gap in dealing with customers. 
