I just got off the phone with Turbo Tax technical support. They do a screen share. What happened is that I had a RL1 (releve 1) for Quebec but an empty T4 from the same employer. Doing the addition in one RL1/T4 instead of 2 fixed it. Apparently its a bug that creates that issue. If you have the same employer and have two T4, only do one, it should resolve the issue. If not contact them and they will walk through the issue with you.
