Filming in low light - getting grainy video - any recommendations?


I've Got It
Hi Everyone,

I recently started making videos and immediately found out that my camera (GoPro5 in linear mode) doesn't do well. It's perfect outdoors with amazing video quality, even before any color correction, but indoors it's terrible unless room I film in is very well lit. If not enough light, even at day time, video has lots of grainy noise.
Audio is terrible too - but I overcame this issue by using external mic Zoom H1.

I'm ready to buy a new camera, if there are good cameras on budget, as I'm currently very limited in time of day I can use my GoPro and even then, it's far from perfect, however acceptable.

So my question - did you encounter the same problem and if yes, what was your solution?

If your camera does well in low light - what's the model?