Virtual machines fail to connect to proper Virtual Network

I have two R710s and a MD3000i configured as a cluster with High Availability on both the Virtual Machines and the file share drive. I have 5 Virtual Machines all server 2003x32. When they roll from Server1 to Server2 four of the five connect properly to the VMExternal network while the fourth connects to VMInternal. I have to manually open Hyper-V manager and set it to the correct network. If I reboot that virtual server after correcting the network it stays with the proper selection. If the Virtual Machines roll back, then it is again back on the internal network even though I have selected the other. Both machines are using the same network names and four of the five machine roll without issues. Any idea as to why this one fails or direction to look would be appreciated.