5.4 for 5.7

Dear All,
I have been working on fine tuning my network, but i am always havineg problems of interference with my BACKHAULS , so what i intend doing or have done is to switch the 5.7 with a 5.4 radios to serve my OMNI’s , i has been working but on one site, it is not stable.
I want to know if i have done the right thing by using a 5.4 GHz to feed my OMNI’s ?
Do some have a solution to it?
I will appreciate your solutions

Did you look at the spectrum in 5.4?

What is the distance?