Raspi 3, Video Stuttering

Hi

I’ve installed Kodi V16 from http://pipplware.pplware.pt/pipplware/di…in/binary. I’ve attached then my Synolgy NAS over NFS and most of the movies are working fine.
But on some the Video is stuffering and it’s important to watch a movie.

When I connect with putty to the raspberry, I can see that the CPU usage is very high:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
478 kodi 15 -5 722956 220004 46060 S 335.9 29.2 298:14.22 kodi.bin

When I open the Movie on my laptop with VLC it’s working fine. Codec Information of VLC shows the following:
Codec: MPEG-H Part2/HEVC (H.265) (hevc)
Codec: DTS Audio (dts )

Has the Raspberry Pi 3 to less cpu power for this kind of movies, or what can I change to get it working?

Thanks for your help.