All cell phones have some sort of built-in speaker. The speaker allows you to hear the voice on the other end of any phone call. However, if the phone's speaker begins to crackle or the volume is not high enough there are a few options available to correct the issues. None of the correction options require you to purchase additional material (unless you don't have a safety pin or paper clip available).
Power down the cell phone and let it dry if your ear has been sweating or if there is excessive moisture in the air. These conditions cause static in the speaker and often create distortion. Wait for the speaker to dry before using it again.
Inspect the speaker on your cell phone. More than likely there is dust and lint stuck to the speaker port. Clean this with a paper clip or safety pin. If using a safety pin be careful not to push too deep, as you may pierce the speaker and damage it.
Disconnect your phone call if the microphone echoes (such as you hearing yourself a moment after speaking). This is due to a bad connection. Replace the call and the echo should go away.
Press the "Menu" button, choose "Options" and bring up the audio information. Choose the speaker option and either increase the volume if you can't currently hear the audio, or turn the volume down if it is crackling.
Things You'll Need
Paper clip/safety pin