PMP450 / PMP 450i SM/AP issue possibly related to Cisco Switches?

We have been having an issue the past couple weeks where we have 1 AP with 3 SMs off it.

AP and SMs are all 16.0.1, AP is 450, 2 SM are 450 and 1 SM is 450i.

Issue is when you reboot any SM; or if an SM loses connection for any reason the other 2 "go offline" for about 5-10 minutes.

We have been able to confirm the radios are not physically dropping the connection; if you are connected directly it works fine. 

We have 5-7 similar networks with varrying levels of AP/SM arrangements. Same Cisco switches, with same configs on the same overall branching network.

If we are connecting directly to CMM4 we don't lose any connection as far as we can tell, no pings are lost(Except the SM that is rebooted).

However if you are outside that, behind the cisco you will lose them for 5-10 minutes and they may not recover.

Each site has a primary/backup so we can confirm at least as far as we and network engineers can tell; the switches should not be the problem. 

We have done the following:

Bypass firewalls, use primary/secondary switches, connect directly, match all settings across SMs, replaced the 450i with a 450(Thinking maybe the 450i's aren't as compatible as they claim and this was only network that was a blend of 450/450i's, now it is all 450s), replaced all SMs in field with different 450s.

We don't know where to really proceed from here.

2 SMs are at about -55 and hit threshold, another is at -80.

We use omni directly 3.6 antennas 11 dbi, sometimes we will use the integrated or a panel antenna depending on application. 

Any ideas?

This behavior is not familiar to anyone here... I suggest you open a support ticket, so we can gather the requisite information to troubleshoot things.

You can go to this page, and click "Submit a request" button at the top of the page.