Is there a sound issue when recording video?

[jma78b]

Hi I've had my S8 since 21 April. I had not noticed before but I had my video recording on the highest setting HAD and have just played them back and there is no sound. Does anyone know why this is? I've put it to a lower setting FHD it works fine.

 

[Targatheory]

Sounds odd, I hope someone answers because I am expecting my S8+ on Monday...