Tired of disconnection problem

Guys i am tired of disconnection problem with mikrotik mAntbox 19s. did almost everything some time it says extensive data loss some time unicast key time out i cant figure out what could be the problem?

That means, that the person is leaving the coverage area of the AP.

no, the customer is on coverage area.

Or device is going “sleep”.
Windows could switch-off WiFi interface to save power consumption. Has the customer this feature switched on?

I have same issue on several locations with different aps..

For example this is my HOME, and the client that says extnesive data loos is a TV who doesnt move inch, and as u can see signal is more than powerful(-48-62), still i get random disconnects for all devices at home, Philips TV, HTC phone, ASUS tablet, Asus Laptop ..

Sometimes its ok entire day, sometimes happens few times a day.

I had 2hspn before, now i put one SXT2 lite, and still happens, and i tried all stuff, changing all channels, setting auto, changing to WPA2 only, increases HW retries, timeouts, setting N only mode, chaging 20 only or 20/40mhz,turning WMM On/OFF, multicast helpers, noise immunity settings, various Router OS versions, using pretty much stock configuration with reseted device, u name it, i tried every tip and trick that available on google or this forums for mikrotik..
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