why am i suddenly hearing weird music on my phone???

[AC Question]

I was listening songs from my phone and all on a sudden I got to hear some weird type of music. I turned off the song but still that weird noise was going on. it was a bit ghostly type like we hear in movies.... and I am sure that I don't have anything like that in my phone.It continued for a while like half an hour ...... was it hacked?????