challenge

running ivms2400 pcnvr software for a couple of years and been happy with it as its suits my needs and i know how to use it but for the last couple of months i have been experiencing no video running w10 lastest update, when you first start the software it works fine, can see live feed and can view recordings but after 30 mins or so when i try to view anything (live or recording) i get no video just a black screen like i have not selected a camera close and restart the software its ok again can even view recordings that were made when there was no video just to add, even with this going on the app can log in and work fine, or if i have a client on another pc that works fine too any ideas?