System Information
Windows 8.1, Nvidia GTX 960
Blender Version
2.75 (sub 0), branch b'master', commit date b'2015-07-07' b'14:56', hash b'c27589e', b''
Worked: (optional)
Short description of error When more than one Track TO bone constraints are active in BGE they start moving wildly.
Exact steps for others to reproduce the error
Open the blend file and delete all blue planes in the scene, then you'll see the random jittering.
Bone parenting the blue plane objects(any object) seems to stop the jittering.