Neogaf : Multiple reports of joycon issues in switch previews.

[Miyamotoo]

NATO said:

Miyamotoo said:
Its seem its problem with strength of left Joy Con signal on some Switch units, hopefully this will resolved with day one update.

Assuming the controllers have the ability to be updated, most do not.

It doesn't need controller to be updated, Switch can be updated to have stronger signal for Joy Cons.