using 3 amped AP in close proximity, 1 ap goes down.

I have 3 AP that I have setup to send internet. They are all on the same
tower. 2 use 60 degree sector panels and the third is on an omni
directional antenna. Each antenna is on a different channel and
different SSID.
The problem I am facing is that the AP connected to the omni antenna
keeps going down. The AP stops transmitting. I have replaced it with
another and the same problem persists. It seems that everything works
well, and then after about 6 hours it goes down.

Please send your suggestions
Thanks

michaelfromm at hotmail.com <"michaelfromm at hotmail.com"> wrote:
> I have 3 AP that I have setup to send internet. They are all on the same
> tower. 2 use 60 degree sector panels and the third is on an omni
> directional antenna. Each antenna is on a different channel and
> different SSID.
> The problem I am facing is that the AP connected to the omni antenna
> keeps going down. The AP stops transmitting. I have replaced it with
> another and the same problem persists. It seems that everything works
> well, and then after about 6 hours it goes down.
>
> Please send your suggestions

Try moving the omni one up or down a bit?