WIFI RB951-2n problems

I have problems with some devices to connect to an AP B/G/N (RB951-2n)

I think that the problems are in the WIFI BOARD, because if I connect the same devices to a VIRTUAL AP (in the same RB951), I have no problems…

ROS 5.26
WPA / TKIP
WPA2 / TKIP

The IOS devices dont receive DHCP Address, and other windows devices, reconnect every 5 seconds (Good Signal, no noise, etc…)

The same configuration in other RBs run without problems…

Any known issue ???

Best regards

Use WPA2 and AES
Never use TKIP with wpa2