That's why it is so important to have a spiritual master to
guide you on the path.
My opinion is regardless of where this sound comes from, don't let
it affect your cultivation.
Some people when meditating, they smell some fragrance smell like
sandalwood josstick tan2 xiang1, it is actually the smell that
deities pour on you, just don't bother it although it is good sign.
Otherwise, it will become hindrance to your meditation.
A scary one that I heard is got this person meditating, then
suddendly some ghosts one by one appear around her flying around
screaming laughing. She scared but still can remain calmness. She
told the ghosts "please don't disturb me doing meditation, I
promise one day if I am enlightened, I will go and save all of
you". When she finished this sentence, all of them disappear. I
think a lot of bad karma are being washed away by this
moment.
No matter, don't let hatred or greed to affect yourself. Don't let
environment control youself.
