Selecting images and audio from list

I am trying to create an app for padi revision for my daughter what i want to happen is when i press next button it loads the next picture in the list and plays the corresponding audio file, i have two lists one for the images and one for the audio files everytime i hit next it increments the list index by 1 and when i press back it takes 1 off the index variable, I use this variable to select the correct image and correct audio file. It doesnt work when i press next nothing happens, can someone point to what i am doing wrong? This is the first thing i have tried to do with app inventor so a little green!

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are you using both the Sound and Player component?

try to use only the Player component

remove the 2 advanced blocks (a list is not a sound component, this does not make sense like that) 

instead call Player.Stop, then set the Player.Source to the corresponding mp3 file and call Player.Play

you also could use only one index for both lists...

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