Forum:Insanity Playthrough Setting

For some reason when I "select an existing ID" to do a second playthrough on my level 50 soldier, the difficulty setting keeps reverting to "Hardcore" even though I set it, and saved it on "Insanity" in the game's starting menu (ME 1).

So I'd launch game, extras -> options -> gameplay -> difficulty insanity. Start new career -> select existing ID. When I start on the Normandy the difficulty is back on Hardcore. I'm just concerned that I won't get the insanity achievement if I set it to insanity only on the Normandy, although still before Eden Prime - any thoughts?