What kind of team are you using, and which NIC has the IP address now? Did you try to remove the team and re-configure it?
intel pro/1000 EB setup as adaptive load balancing. Both nics are on the motherboard. Both say active. Both say team#0, but instead of the virtual nic having the ip number, the first member has it. I was going to remove the team and recreate it, but saw in some forums that the Symantec endpoint protection has had issues with teaming over extended periods of time. If updates to Symantec can knock out a team, I'd rather forgo the server inturruption (had issues throughout the day it happened). But if it was just a fluke, I'll go ahead and recreate the team. Does having a team radically speed up the network aspect of a server?
I'm not aware of any known issue with teaming and Symantec endpoint protection. You can also check with the experts on the Wired Ethernet Community.
As for teaming performance, it depends on what kind of teaming mode you're using. See http://www.intel.com/support/network/sb/cs-009747.htm for details.