I have not found a solution to remedy this problem that has come from Samsung and is probably present throughout the NX range.
Note that you replace the release cable Samsung (micro USB) by any other, I used a male mini jack cable male mini jack (those smaller than for your smartphone) and so I was able to use the remote for my Canon 350D.
Autonomy hast the excellent air, after two months of use in timelapse is always on top.
You can use the power button at the point / trigger and BULB position without turning on the remote control.
In short, perfect.