Streaming stops

I have PMS installed on a laptop that I use as an htpc. I watch films and tv-series through Plex Home Theather (installed on the same laptop). The files are stored on my QNAP HS-251 NAS. The problem is the following. When watching a movie or a tv-show the streaming stops and after that I see the information screens of the item I am watching. When I restart, the item continues where it was at the moment it stopped (I have not noticed this with playing music files). The problem also doesn’t occur for a second time when I want to reproduce it. Then all goes smoothly. It is very irritating.

(For your information: I also have Kodi installed and sometimes the streaming also freezes but in a different way. The image freezes bit the subtitles continue, I have separate files for the subtitles. After some seconds, sometimes longer, the streaming continues but very rapidly until it cathes up with the subtitles.)

Does anybody knows how to solve this problem?

Joop.

PS
When I go to Windows/users/………….logs, I see a long list of logfiles. I don’t know which one is applicable.