all nuendo 6 up to 6.07 have a bug when opening an existent project that contain a TC electronic “PowerCore” VST plugin named “Dynamic EQ” it “neutralized” the channel/group permanently !
no sound will come out of this channel even after removing the plugin from the channel insert
if you try moving the “Dynamic EQ” plugin to a different channel/group it will do the same to the new one and so on, an “infected” channel/group will never work you have to delete it permanently and create a new one instead.
adding new “Dynamic EQ” plugin on a channel insert directly in nuendo 6 will work fine, which means you can NOT edit/mix an existent project from N5.x that contain a TC electronic “PowerCore” VST plugin named “Dynamic EQ”, but you can create a project on N6.x and use the “Dynamic EQ” plugin.

Yes, this is a problem for sure, there’s a whole thread about it already. If my recall is correct it’s a TC problem (and since it’s not supported anymore it won’t be fixed). John.