@BrianDipaolo I'm guessing that you think it is related to STP as there is an event log alongside the port up down? If so, that is totally normal and the STP log is a result of the port going down and up.
What switches do you have and what version of the Meraki firmware are they running?
On the NVRs or cameras (I'm not sure which you say are going down), are there any power saving modes like Energy Efficient Ethernet? If so try disabling them.
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