This is Dr. Christian.
Thank you for the added information. Itching can start as simple allergies and then progress to infections. It is possible that he could have infection but it is so deep in the ear canal (near the ear drum) that you would not see it yet. You can try giving 25mg of benadryl every 8-12 hours for itching. It may make him sleepy but could also help with the itching. I would recommend having his ear checked by your vet so that the ear canal can be examined. If he does have an early infection it will be much easier to treat now rather than later. You can find an over the counter ear cleaning solution at your local pet store that may also help. If you have more questions please let me know.