Workaround for the DLNA disconnection while playin
I am experiencing the same issues with my Samsung SmartTV 8000 series. I am using this as a workaround:
1. Reboot the TV if it was online for a while. After rebooting the TV, the DLNA connections will work just fine.
2. Go to your Samsung PC AllShare software switch to "Play Control Screen Mode". That can be done by pressing the "Play" button in the top left corner (or from the "View" top menu)
3. Click on Refresh to the top right corner while it will detect your TV.
4. After it detects your TV, go back to "File Management Screen Mode", search for your media file. Right click on it and select "Play on another device". You should have an option available to play the file on your already detected device.
5. Enjoy with no disconnection issues.
PS: you will be able to pause/seek from the remote control of the TV. From some reason, only when the playback is initiated from the TV the connection will fail after a while.