RGB led Strip + 4 Buttons + Mp3 Shield

Hi Guys
First of all, sorry for mistake, I'm french.
I'm actually doing a lamp for my girlfriend with a rgb led strip. Everything work fin. I decided to had a Mp3 Shield and 4 buttons so she can push boutons to hear sound. I'm can make the 2 thinks work alone but when I but the code together I have a problem. The arduino to all the For before reading the buttons. Can you help me with the code so that the arduino always check the 4 buttons and in the same time to the fade program for the rgb led strip.

Thk

I will update code tonight.

Math

Post the code you have now.