Comment 28 for bug 1808389

Ok, this is a complex matter. I just experienced this unpleasant feature on my laptop using the above described driver and hardware for the last two days. =>It seems to be a radio transmission issue.<=

The Linux driver as well as the microcode of the WiFi device must be able to cope with the small frequency jumps of the access point. Yes, frequencies are =>NOT<= very stable. This is shown in the logs by the following messages: wpa_supplicant[971]: wlp1s0: CTRL-EVENT-SIGNAL-CHANGE. When this event occurs, your hardware must resync with the access point. The driver as well as the microcode of your WiFi device may or may not support such a frequency jump. In other term they may or may not be able to cope with the noise. The following log message shows that my system was not able to cope with it: iwlwifi 0000:01:00.0: Microcode SW error detected.

What actually solved the issue is re-configuring the access point. I limited the channel width on the 2.4 Ghz frequency to 20 Mhz to avoid interference with other access points in the area. In addition I defined a precise channel for the access. For the channel selection, prefer channel 1, 6 or 11, since they do not overlap. Now my connection is stable and my logs are clean.

For the 5 Ghz network, these problem might not occur as frequently as on the 2.4 Ghz one, since it is less used. In case similar issues are faced, proceed similarly.

Hope it helps, Illi

Same comment was also posted in the dupplicate of this bug.