MP3 Key Changer
Full user review
"The Best Key Changer for MP3 Music Out There!"
Very easy to use. Also changes tempo! Others that I have used in the past have distorted the music at times, this one doesn't distort!!
It is a bit slow, but worth the wait.
I have purchased 4 or 5 key changers, now I have one that works perfectly...and as a bonus, it also changes tempo. This is the best.