Has anyone tried this workaround for sound?

[Foster Kane]

http://dslrhd.com/2010/04/dslr-audio-trick-for-canon-7d-and-t2i/

I was also thinking do I just need Y splitter that I can put into the mic jack of a T3I so I can put headphones and a mic into the DSLR?

 

[Chris Santucci]

No headphones.

 

[analog_addict]

Just install magic lantern to get AGC. Mic goes into the mic socket and you can monitor live through the USB out with magic lantern.

 

[Chris Santucci]

The Juicedlink preamps employ this technique to enable manual audio control in these cameras.