MESH problem: disconnected, no beacons received

AP2
Dec/16/2012 17:46:12 wireless,info 02:0C:42:26:7D:C4@wlan_ap_mesh: disconnected, no beacons received
Dec/16/2012 17:46:13 wireless,info wlan_ap_mesh: data from unknown device 02:0C:42:26:7D:C4, sent deauth
Dec/16/2012 17:46:13 wireless,debug wlan_ap_mesh: 02:0C:42:26:7D:C4 attempts to associate
Dec/16/2012 17:46:13 wireless,info 02:0C:42:26:7D:C4@wlan_ap_mesh: connected, is AP, wants WDS, wants bridge
Dec/16/2012 17:46:39 wireless,info 02:0C:42:26:7D:C4@wlan_ap_mesh: disconnected, received deauth: class 2 frame received (6)
Dec/16/2012 17:46:45 wireless,debug wlan_ap_mesh: 02:0C:42:26:7D:C4 attempts to associate
Dec/16/2012 17:46:45 wireless,info 02:0C:42:26:7D:C4@wlan_ap_mesh: connected, is AP, wants WDS, wants bridge
AP1
Dec/16/2012 17:46:13 wireless,info 02:80:48:54:BB:B7@wlan_ap_mesh: disconnected, received deauth: class 2 frame received (6)
Dec/16/2012 17:46:13 wireless,info 02:80:48:54:BB:B7@wlan_ap_mesh: connected, is AP, wants WDS, wants bridge
Dec/16/2012 17:46:39 wireless,info 02:80:48:54:BB:B7@wlan_ap_mesh: disconnected, no beacons received
Dec/16/2012 17:46:39 wireless,info wlan_ap_mesh: data from unknown device 02:80:48:54:BB:B7, sent deauth
Dec/16/2012 17:46:45 wireless,info 02:80:48:54:BB:B7@wlan_ap_mesh: connected, is AP, wants WDS, wants bridge

Hello,
I have two AP “Access Point” that about every 1.5 hours disconnecting!
I have configured two AP as indicated on the guide http://wiki.mikrotik.com/wiki/Wireless_WDS_Mesh works perfectly except for this problem!

If I configure the two devices one as AP and the other as station they work perfectly without errors!

I have attached an image where you can see that the signal is good.
signal.jpg
In your opinion what can be the problem?

Thanks for your help.

Did you solve this problem? How?