There could be many reasons for this. Most often we feel "blocks" due to stress. The best way to relieve that, and find the cause, is meditation. There are various forms you could use to help. If you think it is something bothering you I would try focusing on that as a question. If you are having difficulty concentrating, try "mindful meditation" or a simple deep breathing meditation.
If something is trying to communicate with you and you have issues hearing, try doing some work on your chakras, more specifically your third eye. If you need examples of these, feel free to mail me :) Best of luck!