[quote=Beta]
Sounds to me like someone didn't do all the loyalty missions or upgrade their team properly.Or simply picked all the wrong people to do each leg of the base.Garrus or Miranda for leader roles.Tali or Legion for Hacker.Jack or Samara for Biotic.Mordin for Crew Escort.
[/quote]

and upgrade all of the equipment as well as have a good strong line.