Direct Outs and Mutes

I'm wanting the direct outs to be unaffected by mute groups. I'm using the direct outs to feed an Aviom card and want to be able to use mute groups without them also muting the Avioms, just as you would on an analog board by setting the mutes to be post-aux/pre-fader. The direct out points are set for pre-fader so I'm not sure why they're being muted and I can't find anything in the manual that tells me where the mutes are effective in the signal chain. Any help?