With MR55 look at power saving. I found the following issues:
26.8 firmware, Android devices deauthenticated and had to try several times to reauth, regular issue
27 firmware, laptops with WiFi5 NICs, packet loss when not plugged in to mains power.
I run 27 firmware now and changed WiFi power setting to maximum performance in Windows 10 for some laptops and replaced the 8260 NIC in another with an AX200. AX201 also works perfectly, so do non Intel WiFi 5 NICs
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