Emitter shows before and after X frames. Render>Emitter off glitching?

Hi guys, I´m going crazy with this.

I have a 2000 frame animation.

I have a particle sphere emitter to play it´s emission at frame 1300. End particle life at 1310. All good, it plays.

From frame 1-1299 I CAN SEE the emitter.

If I go to the emitter settings>Render>Uncheck Render Emitter… I can still see the emitter before and after these frames.

I´m going mad. I cannot click on visibitility to camera (cycles´s settings) the object and particles completely dissapear.

I´ve checked on materials… The emitter has no materials. The particles emitted have an emission colored material. Particles are regular icospheres on the same layer away from the camera.

What else am I missing?

Thanks.

(works normally on any other scene).

Bake simulations are cleaned…so?