NSTREME dual problem

I have problem with NSTREME dual.IF tre troughput is 2Mbps / 2Mbps everything is OK.If the throughput is higher tnan 3 Mbps te latenci will be more than 1000 ms and the connection has been lost. I check the nstreme dual statut and it is connected and data rete is RX 48 and TX 6 mbps.

Hardware is PC 2,4 GHz intel and wlan cards are CM11 on 22 dB.

Where is the problem?

Post your configs so we can see what you have going on.
With out more info from you I would be guessing.