it's not the soft release button giving the prob
rather, it is that the rx1 when fittted with the soft release button, when placed inside a bag, it is easier for the other items inside the bag to depress the shutter release button with the soft release fitted on. the depressed button drains the batt.
if your bag is full of contents, even without the soft release button and the shutter button is depressed, the same batt drain will happen
i put my cam sitting straight up inside the bag without any above, and compartment it, putting all other stuffs in the other pockets. so far no issue, since no item can possibly depress the shutter release button with a soft release.
it's how u manage the placing of the cam inside the bag.