As mentioned above, there can be two causes, one is when the DFS mechanism is looking for radars, if you use a frequency in the DFS range. Simply setting a different frequency will resolve it.
The other one is also software related, multiple wireless fixes for the ARM platform were recently released. Make sure you upgrade RouterOS.
There is no known hardware issue with RB4011 and 5GHz.
This definitely IS a hardware issue. Despite the fact My device is used less than a month, 1 year from purchase date just passed and most likely no one will do anything regarding failing device.
However, I am sure that everybody else has the same issue with this particular device model and 5GHz interface.
Why? That's why:
1. I managed to sort out 1st problem with the frequencies. Only 5420 GHZ actually works with all devices. Choose anything else from the list and You will have issues like You cannot connect or SSID is simply gone
2. Interface works like a charm with good speeds, even when loaded with everything I could from 3 WiFi devices with TCP transfers above 300 MBit/s both ways for few hours. Even after this test it worked for 2-3 days. But then 5 GHz SSID simply disappears. No logs, nothing. You can enable/disable it, but nothing helps, unless You power off device and power it back on. The it will work 2-3 days, and then same problem again. The problem is the same 4 times in a row so far.
3. And the most important thing. When it happens, if You look under System Resources > PCI, it clearly says, that there is an unknown device made by Atheros
Screenshot 2021-04-01 at 22.09.54.png
CALLING OTHERS: Can You confirm that this issue looks the same on Your devices?
So, Normis and MikroTik in general. Will You still ignore this and continue saying that everything is cool with this device?
I honestly don't know what to do now, as this is the only device in its kind and I need exactly this pack of features, but 5GHz is unusable.
Even if for some magic reason You WOULD replace my faulty device, I don't believe that the new device will not have the same issue.
I definitely doubt on buying another one, which most likely will fail the same way.
I hope MikroTik will confirm this issue and recall these faulty devices for everybody who bought them and replace with working ones. Will You?
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