The fix is very very easy:
1) Go into X:\\Files (x86)\\Mass Effect 2\\BioGame\\CookedPC folder and COPY the following files:
BioH_Assassin_01_LOC_XXX.pcc
BioH_Garrus_01_LOC_XXX.pcc
BioH_Convict_01_LOC_XXX.pcc
(XXX depends on your localization. For Example, for the Italian version is ITA)
2) Paste the files you've just copied in X:\\Program Files (x86)\\Mass Effect 2\\DLC\\DLC_CON_Pack01\\CookedPC folder and rename them as following:
BioH_Assassin_01_LOC_XXX.pcc ---> BioH_Assassin_02_LOC_XXX.pcc
BioH_Garrus_01_LOC_XXX.pcc ---> BioH_Garrus_02_LOC_XXX.pcc
BioH_Convict_01_LOC_XXX.pcc ---> BioH_Convict_02_LOC_XXX.pcc
Make sure you copied the files that contains 01, not the files that contains 00 or it won't work!