WLE600VX get 802.11n to run

Hi all,
I try to get the 802.11n Mode to work on my system, (ac works)
but it will not run with higher speed than 70MBits.

hostapd.conf_n_Mode.zip (6.2 KB)

See attached host file for more information.
One of my neighbours has a lot of bluetooth clients (lamps and so on) running.
Is this maybe the problem ?
Best regards
R.