Nimbostratus
MVPdean0Things I would check.
1. When you run a tcpdump on the F5 are you seeing the connection arrive?
2. If the firewall is issuing a RST to the F5 that means the F5 is not sending the connection anywhere and the firewall is most likely resetting the connection after the protocol timeout has occurred.
3. Check for asymmetric routing on the firewall and F5.
If these do not reveal anything to you can you please provide a topology and a configuration output for your F5 while redacting any sensitive information so we can have a look and see what we can find?