URGENT:AP show but cannot associate after 30min

I had to setup an urgent AP for an international surfing contest here so journalists, etc. can have internet access with laptops. With no security they can all just connect. It works fine for about 30 min, then no traffic flows. If you disconnect, you can see the AP at full signal strength, but cannot connect to it until a reboot.

Any idea? I changed pre-post 2.95, country, frequency, BG or Bonly, but same problem.

Thanks
Ekkas

make support output file when noone can connect to the AP and send it to support@mikrotik.com

Have you looked at the log file - what does it says when they are trying to connect to the AP?