Random Stop on Kodi All Version

Hi, i have a smart box tv “PLUNK S”
CPU Rockchip RK3188 quad-core Cortex-A9 a 1,6 GHz
GPU Mali 400 at 600 MHz
RAM 2 GB
8 GB rom
webcam
Bluetooth 4.0, Wi-Fi b/g/n
4 USB / 1 OTG
slot Mini SD
HDMI
AV out
OPTICAL
ethernet

unluckily the Itali­an company has failed then i can’t get support for it.

actually i have a fw based on Android 4.4.2.

i can’t use Kodi and other similar apps because when a movie is playing, after a random time the movie stop and return to menu.

i have already tried to use different version, nothing is changed.
i have checked with root and without root
i have checked network and buffer when stop happen, but it’s all ok.
i have tried with different add-on
i have flashed two original roms
i have done an hard reset
i have changed Dns

i have done all this, but nothing is happen.

i can use youtube, Netflix and others apps, while kodi & similar no because the movie stopped after a random time, usually each 29min.

Someone can help me please? Confused