Trek Store Tablet : my grandma mute the sound, need a screenshot of the sound Program :)

Hey Guys pretty funny problem, we bought our grandma this table. In the bottom you see the Speaker Sound Program witch she is using for hearing music. I need a screenshot of this player cuz i dont have an Andriod device. That i can explane my Grandma by Telefone with bottom she needs to klick.
My Grandma silenced the musik at all nad have no clue to bring it on againe.
After 30 min of trying to find the volume levler by Telefone, i come to you


What i need is the pictor of the master volume levler and a screenshot of the speaker program wiht the volume lvler thx guys .