Try out remapping hot pixels.
Google for it:
Hot pixel remapping canon
Did helped a lot for raw video on my canon 6d.
If I remember correct you need to remove the lens, place the bodycap on the camera and then perform a manualy sensor cleaning from the Canon menu.
It helps to heat up the sensor a little by using liveview on iso 6400 a few minutes, right before doing the manual sensor cleaning.
On iso 6400 there probably still will be soms (hot) pixel noise, which is easy removed by most raw editors. Like RawTherapee, it has a hot pixel remover function on the raw tab