802.11n and laptops

Hello
this is the first time I write here, due so far the wiki and the forum had all my answers,
But this days I am confused about 802.11n I have made some test with laptops and the results are frustrating
I tried with one Sony Vaio and an Imac with Leopard with same results

I test to upload and download from and to a fileserver an the maximum speed is 30 mbps and is fluctuating all time from 1 mbps and 30 mbps
I am using a RB400 680 Mhz cpu and a a R52N with two antenas attached
The laptops are 10-15 meters far.
Mikrotik Os is configured with chains tx,rx 0,1 checked, and AMPDU Priorities are checked 0,1
I tried with several combinations of above but nothing that raise up the speed

Please, can someone to help me and explain me what is happening and if it is normal? is it possible go beyond 30 Mbps? or mikrotik has not developed a better version of 802.11n?

Thanks in advance

Hi !!!
anybody want to answer? :open_mouth:

thanks

Hello again
nobody happened the same?