I cant seeem 2 get sound on my new "WD TV mini"

i just brought a new “WD TV mini” player plugged in the yellow and white cable into my tv but i seem to not be getting sound out of movies i know that have sound there,

any advice would be a really big help thanks

Could be a bad unit or a bad cable. Do you have another set of cables you can try? You did make sure they were secure and plugged into the right spots correct?