I am reading a good book that I bought a long while ago called A Message from God by Retha and Aldo McPherson. It is a book that challenges the stagnant Christian--a Christian who is complacent, and not on fire for Him.
Even though I am not that far in the book, I read a paragraph that made me realize why people do not always hear God's voice, and are not completely in-tune with Him.
"The presence of sin in our lives is like a wall between God and us, keeping us from hearing His voice. When people say they feel like their prayers are bouncing off the ceiling, I know it is impossible. It's not the ceiling that keeps you from making contact with God. It's sin; those things that seem insignificant in our eyes, like jealousy, bitterness, your own strong will, and pride. God hates pride."
Do you have any unconfessed sins, which are keeping you from hearing His voice? Ask God to forgive you of your sins.