After being on this site and reading so many posts from so many amazing parents, I have learnt many things. I have been watching my difficult child closely to watch for hidden triggers that i may not be aware of. I have noticed the following things: 1) When he wants to talk to me in the car the windows have to be up, the radio has to be off and my easy child has to be silent. He is not able to get his thoughts out if there is any noise. 2) He has always hated the sound of motorbikes passing the car. 3) With family gatherings when there is lot of noise he has meltdowns a lot. 4) When I do respite with an autistic boy that makes constant noise, after a full weekend my difficult child is in constant meltdown mode. Could this be Auditory Processing Disorders (APD)?