Rb Metal 2 shpn Problem

Hi I have a problem or several problems with my Rb Metal 2-SHPN which all my friends have high DBM between 75 ~ 90 and this causes the very slow internet

Another problem is that disagreement with the specifications of this product would cover more than 4km RB smoothly.
My problem is this buy a TP-Link TL-WA5210G to use as a client my problem is that after a few minutes unable to detect the signal once the signal so I set it again loses the TP-Link works perfectly and I tried it on my house with no problems I just listed the same way 75 ~ 90dbm these testing on all channels

The distance between me and my RB Metal TP-Link does not exceed 950 meters.

Sorry can not speak English but this is the only place I could find help because I need it urgent

Try this version What’s new in 6.22 (2014-Nov-11 14:46)

Improvement: new firmware for Metal RouterBOOT 2SHPn to improve increase wireless stability


Luck.

Try this update

new RouterBOOT firmware for Metal 2SHPn to improve wireless stability

http://download2.mikrotik.com/routeros/6.22/all_packages-mipsbe-6.22.zip

Try this update
new RouterBOOT firmware for Metal 2SHPn to improve wireless stability

http://download2.mikrotik.com/routeros/6.22/all_packages-mipsbe-6.22.zip