Sounds if its conserving power does this happen whether you are running mains or on battery.
Mine does just the same when the lid is closed or left for more than 5 minuets, as far as I know you can alter the settings for this.
Fujitsu Lifebook P727 laptop review
Lightwell software lets you create mobile apps without using code
Best value Mac: Which is the best £1249 Mac to buy
Comment désactiver les programmes qui s'exécutent au démarrage de Windows 10 ?