I have to confirm this. I've tried r1193 build for the RT-N16 and I experienced similar behaviour after a couple of minutes of using the wifi (wireless N + WPA2 AES). The wifi led on the router was blinking as if it was a HDD led and the speed dropped down to < 300kBs and connection was unstable.
When I changed the wifi security to open system with 54g limit, the behaviour was the same.