Thanks for the update @James_Hanson!
Is the Linksys switch a managed switch?.
I usually like to mention that we’ve tracked a number of issues to in the past to managed switches(examples: here, here, and here).
If it is, would recommend enabling flow control on the switch, as we have seen that settings resolve a number of issues for other users in the past.
The simplest way to confirm whether the switch (managed or not) is contributing to these symptoms would be to temporarily test with the switch removed from your network. Whether things improve or not, the results of that test would be a great data point.
Regards,
Dylan