Impulsive behaviour towards babies & toddlers

Hi

Our son is 10 yrs old and has diagnoses of ASD and ADHD. We are desperate for help with his impulsive behaviour towards babies and toddlers. He wants to grab them, squeeze them or make loud noises at them. This is of course highly socially unacceptable. We have had three incidents which have been awful and are now on incredibly high alert any time we are out. It is narrowing our world even more and my partner is now very reluctant to take him out anywhere where there are other people. We have talked to him, done a Social Story, worked on distraction techniques, praised when we have walked past without incident etc etc. I have contacted school, the children's Disability Team, paediatricians, GP, specialist ADHD consultant and more but no one has any ideas or suggestions and we are becoming desperate. 

We have tried to unpick the reasons for the behaviour - babies and toddlers are less predictable than older kids and adults and he has never liked the sound of babies crying but this physical reaction, especially as he grows older and stronger, is really challenging.

Anyone else had this to try and mange? Any ideas very gratefully received.

Thank you, Louise