Sound fails randomly

[Agusilvad]

The sound fails randomly. If a video is paused sometimes when you activate it again, it plays without audio. Often neither calls nor warnings have any ringtone or sound.

[Dacy]

My sound fails every few days, iv had this phone just over a week, iv had to delete all my music which was over 300 tracks, I have done another factory reset set and still does it, I'm taking the phone back its absolutely rubbish, I'm so disappointed, I'm going to complain 

[Agusilvad]

I am also very disappointed. Unfortunately I am currently in Venezuela and I cannot return it. I switched from LG and the difference is huge and not for better. 

It is the first Sony product that leaves me disapointed.