Canon Rebel T2i Quick Start Manual page 116

Why not plug the receiver into the Camera?
The XVX kit comes with a XLR to 1/8"
adapter to plug the receiver straight into the
input of a camera.
Do not use this with the Canon T2i or any
other DSLR camera that has automatic
volume control on the input. The recording
will be constantly distorted.
In this picture, the adapter is used with the
Sony A7R camera. Both the Sony A7R and
A7S cameras from the CDA depot have
manual volume control and can be used
with the adapter. See the A7R guide for
details.