I'm using a RB951G-2HnD device, i've configured it as a simple AP ( "Home AP" setting in the quickset page ) .
All my devices can connect correctly to the wireless SSID, but when two host ( a raspberrypi 1 and a alienware m11x laptop ) try to connect, i see on the mikrotik log "Unicast key exchange timeout" and the host fails to connect to the SSID network .
Thi issue appears on both the stable and RC firmwares, with the same error log .
The rPi is running openelec 7.0.3, the wifi module is realtek r8712u :
The Alienware laptop is running LinuxMint 18.1, and has a Broadcom Device 4353 (rev 01)(14e4:4353) 802.11a/b/g/n MIMO device .
I've seen that this issue is reported from many people, without a proper solution . http://forum.mikrotik.com/viewtopic.php?t=25820
Please let me know if you need further test \ logs .