-The strange radio

My name is Alex.When I was around 10 or 12, I don't generally remember that, I had an odd experience. At the time, I was sharing a room with my sister. We had lofted beds and i slept on the top one. We had this radio and when you would press the button to turn it on, it would "click" and a red light would appear. Our beds were on one side of the room and the stereo was on desk on opposite side. One night I was woken up by the "click" sound that the stereo makes when the button is pressed. I recognized the sound and sat up in bed. I looked over at the stereo and the light turns on. I look over at my sister and she is sleeping soundly (her bed was under mine yet opposite, so I could see the top portion of her from my bed).   

The stereo is playing that background noise that it makes when it isn't on a particular station. All of a sudden, I can hear somebody saying, "run," coming from the stereo. Only single word, "run away". first is starts off soft and gradually gets louder,until it becomes a yell, "RUN AWAY, RUN AWAY,RUN AWAY ". 
It took around 10-15 seconds to build up to yell, and then it died back down to a whisper. I thought this was just my imagination. I tried convincing my self that is was just an imagination.I had almost convinced my self until it stopped.After the voice died away the stereo went back to static .After that i thought it to be a wild imagination and tried to go back to sleep but my as i laid down i again heard the "click" and it again started.This time it was just whispering my name "ALEX,ALEX,ALEX".I gazed at the stereo for a couple of more minutes, i was too scared to move and saw back at my sister and saw she was still asleep, finally i laid back in bed, covered myself with my sheets, and forced myself back to sleep. 
At morning the first thing i did was i asked my sister about this she said she had not heard any radio voice.I got goosebumps when i saw the radio and there was no battery in it.  I view myself as a normal person, yet I had no possible clarification for this. Freakiest thing that has ever happened to me 

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