link extension (repeating by SM with AP through switch.)

This is the toplogy of my link extented to get a customer where the base station can’t reach.

For my repeater site i used a SM and two AP’s connected in a switch This is my repeater link configuration:

AP0 in the CMM 172.25.12.1

sm 172.25.12.2
AP1 172.25.12.4
AP2 172.25.12.5

sometime all canopy’s pluged in the switch time out at the same period with same duration(time) almost 30-45 msecond,while the AP0 in the CMM has no problem.
or AP1 and AP2 are timing out at the same time while the SM 172.25.12.2 is pinging perfectly the AP0.
I would like to know what can be the main problem then how can i do to solve it?
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as a technician in radio frequency domain ,i would like to know more about this equipment (canopy), bcos it’s ths one we are using for our network ISP.

if encryption is turned on, it resets every 24 hours to get a new code. That could be your problem. I don’t know of anything other than that or a power failure that could reset multiple units on a site.