Have him tested for Tourette's Syndrome!!! Grunting, ticking,etc are all classic signs.
Do NOT believe what you see in the movies about Tourette's!
My little brother was diagnosed many years ago and he will be the first one to tell you that every movie or show out there exaggerates the disease. lol
It's pronounced: tour retz
You might try giving him some Vitamin B6 and Omega 3-6-9 ,it has helped my son with his learning. And my son was on drugs for ADD and ADHD until he started to have Seizures.Now he has to take a lot of medicines for his seizures and had Surgery in June of last year to try and help them by having the VNS put in and still having Seizures. The ADD and ADHD also Bipolar drugs they give can cause Seizures.
Don't take no from the Doctors when it comes to having hi looked at for everything to make sure something is not being missed and not treated for the right thing.
talk to the doctors and ask them to send him to see a neurologist so they can make sure everything is OK with his brain.Many doctors these days more so say every child is ADD or ADHD with out checking everything else and parents don't know better. Blood work should be done to rule out things also EEG and MRI. Also look at what is going on with the family ,like have there been changes in the family,are children being mean st School.
If he is on drugs for his ADD they do have side effects that can change them and should be looked at to make sure he is not having any of them.again blood work EEG.