I bought 4 cameras C100 - V1 variant, 2 of them work normally and get enough wi-fi signal, while the other 2 half meter from router have minimum signal of bars.

In addition, all cameras are on fir. ver. 1.0.17, but only one camera offers me a message to update the fir, and the other 3 do not show this message.

And what,s more, the camera that shows the update message does not want to update to another version?

Is there any solution for cameras with a poor signal and solution to manually update the firmware on all 4 camera, thank you.