We recently switched out our router to a Fortigate 90E. Ever since then, we've been experiencing intermittent ACK not received issues. I can have 10 calls come in fine and then one drop after 32 seconds and then the next 10 work just fine. The Fortigate is configured to have a public DNS server as primary and our internal Windows Server DNS as secondary. When I run wireshark across the interface, I do notice a few TCP retransmission requests. Any ideas on how I can figure this out? Thanks!