Boe,
All mics need help getting up to a certain level. Your camera has a mic input. That should work, but...
Wait a minute. Your camera shows stereo meters, but this site says mic input is mono.
http://reviews.cnet.com/digital-cameras/canon-eos-rebel-t3i/4505-6501_7-344...
::sigh::
The cable you already have may still be a problem. There's probably a pad in it to know the line level down to mic and the connectors could be wrong. Contact Trew Audio/Remote Audio to confirm. Tell them what you have and what you want to do. They make a variety of custom cable solutions.
You run into this when using non-standard audio interfaces. It's just the way things are.
Regards,
Ty Ford
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