USB button import not working EX4100

After the latest firmware update the USB Import button is no longer working! This is one of the most convenient features of this NAS and now is just more trouble from this thing.
Symptoms: After connecting a camera the power button flashes then stops as usual and the front usb import button lights up as usual, then after pressing it, it starts flashing as if it was reading from the camera, BUT it stays like that forever with nothing actually being copied into the /shares/Public/USB Import/
If I insert a thumb drive it doesn’t even start flashing (as if reading) after pushing it.
Any ideas how to resolve this? I’ve rebooted twice, ssh directories are readable and writeable. What is the process that starts the copying into the …/USB Import directory ? BTW the camera and USB drive are actually mounted when connected. So I know that the hardware itself is working and the automount processes work. It is only the push button that in some cases just doesnt work and in some others it only flashes. There’s no log errors, no nothing saying anything is wrong. And these are devices that were working just fine before the update.

These @$#% firmware updates are a russian roulette! My other single bay needed a full restore after all shares became read only!

The problem seems to be that a runaway backup process on usb port 1 keeps on running despite rebooting the ex4. Anyone knows how to identify the process so i can kill it? The gui says the job is running but i cast stop it or remove it because the trash button is grayed out!