sNAT to Windows server and port collision

I tried setting the f5 to always change client port, as this should have caused the f5 to use a new port that wasn't in use, but instead it makes the problem worse, I see the f5 use try to reuse the changed client port in < 1 second, again I assume this is because the f5 sees a full close.

 

 

see from above from my first post. I prefer to have the option to maintain ports though as it makes wireshark views of the f5 tcpdump a little less painful.