The concept is very nice, but the trial and error type of gameplay becomes quite annoying after a while. I think to improve this, you could slightly hint in a way where you are supposed to switch channels on a level, like an arrow or a small "puddle of static" on the ground. Another way to fix this would be to show a small preview of the next channel somewhere, or at least to let the user switch back fast if they end up above a death zone.
Thanks for feedback. I decided a bit different thing. Now + and - for switching channels have their own cooldowns. So you can switch to other channel and then switch back immediately. Also I added Pause (Esc or Q) and you actually can switch channels right during the pause.
I understand that this mechanic can be a little complex, so now I'm working on sort of tutorial (plus changing levels to be more interesting in general).