Traceroute to F5 showing weird results

Hi,

Users are complaining that outlook is freezing up / not responding when doing anything, and hangs for about 10 seconds before responding. I am running a traceroute to an outlook email server which is through an F5 and seeing this result:

RTR1# traceroute vpn 30 10.220.23.5                                                                                                                                            
Traceroute  10.220.23.5 in VPN 30                                                                                                                                                        
traceroute to 10.220.23.5 (10.220.23.5), 30 hops max, 60 byte packets                                                                                                                    
 1  10.38.32.194 (10.38.32.194)  4.411 ms  4.434 ms  4.452 ms                                                                                                                            
 2  10.220.1.18 (10.220.1.18)  5.011 ms 10.220.1.14 (10.220.1.14)  0.859 ms 10.220.1.18 (10.220.1.18)  5.036 ms                                                                          
 3  vip.123.com (10.220.23.5)  0.631 ms  0.641 ms  0.713 ms                                                                                                                
 4  10.220.23.103 (10.220.23.103)  884.057 ms !H  884.067 ms !H  884.068 ms !H                                                                                                           

Why would I see an extra hop after my destination is hit? And why is it causing massive latency? The server is in the same physical location as the source of the traceroute.

My understanding is that the 10.220.23.5 IP is an F5 IP.

Any help is appreciated.

Thanks