Unchanging WiFi STA RSSI value - is this a sign for WiFi problems?

[PanicanWhyasker]

Hi,
I'm using ESP-IDF v3.2 and my ESP code connects to a standard WiFi AP (a Linksys router). It is a WPA2 network with DHCP, pretty standard stuff. A lot of the times the connection fails at some unknown point. I'm troubleshooting where exactly.

Sadly this happens "in the field", in a different country even, so I don't have much info and can't get hold of the debug output on the serial port, however what it seems to happen is that the WiFi scan finishes, the expected network SSID is found, and a connect is attempted, which usually fails. I'm told the AP is not far away, so reception shouldn't be a problem.
Yet, in a few occasions the connection was OK, and the device sent some telemetry data to my server. I have these two log files. The telemetry includes, among other things, the RSSI value, obtained through

Code: Select all

esp_wifi_sta_get_ap_info()

and the field

Code: Select all

wifi_ap_record_t::rssi

This is where things get strange. In both log files, the RSSI does not change for the entirety of the logged data. The device sends packets several times per second. In the first log file it is stuck to -69, in the second it is -76 (throughout more than 5 minutes!)
As I believe any seasoned ESP32 dev would attest, the RSSI changes rapidly even in a calm environment, with no changes of distance to the AP or environment. Essentially the lowest 2 bits are random noise. Yet in this case the RSSI is fixed.

Question
Is this "stuck RSSI" quirk indicative of any problem with the WiFi connection? I was hoping that this clue can shed light on why the WiFi connection fails most of the times. Any troubleshooting suggestions are kindly welcome!

[PanicanWhyasker]

Any ideas?