The Micro Spider manual does not give any details on what microphone lead to use. Should it be Tip, Ring and Sleeve (TRS) or Tip and Sleeve (TS)? I know that many TRS sockets are wired to accept a TS jack plug, but I don't think the reverse is true.
In fact, the manual should specify the jack connections for all of the sockets... except, perhaps, for the guitar socket!