Asus ZenPad 3s 10 audio problem


Jul 6, 2017
I recently bought this tablet, less than two months, and since then the audio hasn't worked well. For instance videos in Facebook, YouTube and Netflix plays but no audio at all, Amazon music doesn't sound neither; Thought the the built-in speakers nor headphones. It reproduces because you can see the progress bar moving, and if the Asus audio wizard is opened you can see the "sound bars". It's random and usually I closed all apps and try another app/video, then go back to the original video i want to watch.

I did a factory reset by the problem stills there, few days ago I got a system update from Android 6 (factory) to 7 and didn't resolved the problem.
I have the option to send it to "repair" under guaranty but I may get a refurbish one, and I hesitate to do it if this is not a hardware issue.

Any ideas?