He is not autistic. He responds to songs, claps in time with them, laughs and interacts. BUT I bet he is having a slight hearing loss. Take him to an ENT for a full hearing test. He may not hear all spectrums of sound or he may not be able to process multiple sounds at the same time. Even deaf children babble, btw.
If the hearing test says he has full hearing, then ask for an early intervention evaluation by calling your local child care resource and referral agency.
And to those that said not to worry, you MUST worry about his hearing NOW. The longer it goes the longer any delays will be. So, at the very least have that evaluated. He DOES have signs of lack of hearing.
I work with children for a living, and we are trained to look for things like this, so I know what I am advising you is exactly what I would tell you to do if you were one of my daycare families.