high cpu at KODI/SPMC

Hi,
I got the MK12 device with not the most update firmware and couldn't run KODI 14 software. so, I upgraded it to the latest firmware MK12FW_150320.
now, it can run KODI 14.x but I have strange problem, device CPU is almost always on 100%. even when I don't touch KODI and it suppose to be idle. I have 2 devices, one with the current firmware and the other with the 14.x unsupported. both of them have CPU around 100%. even with SPMC that suppose to be less heavier than KODI.
this makes the device warm until it may give me a black screen and only return to normal when I unplug the power and let it cool. it also effect the device performance.
the weird thing is that I have a much lower device with RK3188T CPU and with the same KODI version exactly and with the same plugins and skin it uses only 0-5% CPU when idle.
please advice.
E
I got the MK12 device with not the most update firmware and couldn't run KODI 14 software. so, I upgraded it to the latest firmware MK12FW_150320.
now, it can run KODI 14.x but I have strange problem, device CPU is almost always on 100%. even when I don't touch KODI and it suppose to be idle. I have 2 devices, one with the current firmware and the other with the 14.x unsupported. both of them have CPU around 100%. even with SPMC that suppose to be less heavier than KODI.
this makes the device warm until it may give me a black screen and only return to normal when I unplug the power and let it cool. it also effect the device performance.
the weird thing is that I have a much lower device with RK3188T CPU and with the same KODI version exactly and with the same plugins and skin it uses only 0-5% CPU when idle.
please advice.
E