How to break the habit for 7 month old baby for listening to music when drinking milk? Without music she cannot drink.

I reckon the only way to break a habit is to gradually -- in this case take away the music slowly as she feeds. For example, you can switch off the music after a few minutes and see if she responds. Gradually do this everyday, taking away a few minutes of the music each time she feeds. Alternatively, you can replace music with your singing or you chatting with baby. This is a far more convenient and easier alternative compared to having music play around her all the time. Singing or chatting to baby during nursing can also be a great form of bonding :)