When i use my tv as an external monitor (hdmi screen extend) it workes fine until i choose my tv as default speaker. then all my videos starts to lag and there is no sound what so ever. When i was using windows 8.1 i never had this problem, but when i upgraded to windows 10 this problem appeared. i hope it is just some settings i dont know about.
here is a link to show the problem: https://youtu.be/Um0hW3ifEns
I solved the same issue I had since upgrading to Windows 10:
I looked at the advanced properties for the HDMI playback device in Windows 10 and the setting was defaulting to 16 bit DVD quality and on this setting the video on the external screen was choppy and there was no sound. I changed the setting to 24 bit 48000HZ (studio quality) and the sound immediately started to play and there was no longer any lag to the video playback.
