Remove phantom power from mic line

Once the "power" is on the line there is very little you can do with out using isolation. Typically an isolation transformer would be used for this.

That's the part in the DI that seems useful in this instance.

Perhaps you can find another input on your live sound board?

For example; why not use the line level outs of your computer audio box and then use the line level (unpowered) inputs on your live sound board?

Is that a possibility in your specific situation?

best regards,
mike

I like Mikes idea of using an alternate output (from his first post), and would approach it from that angle first.

Another option would depend on how many mics need phantom at any given time.

If you are only using 1 or 2 mics that need phantom (at one time) then maybe you could look at getting a 2 channel pre for those mics. Turn the Phantom off at the board, and only turn it on at the Pre feeding the mics. Of course, the balanced outs from the pre could go to your board so your workflow really doesn't change.

If you don't want a full PreAmp, you can buy a dedicated Phantom Power box. I don't know if this one is any good, but here is an example: http://www.sweetwater.com/store/detail/SPhantom/