My phone's sound is weaker than before. How do I fix it?

@ksm36497 could just be a clogged speaker mesh. Clean it with a toothbrush. If that does not do anything, consider replacing the speaker. Here is a guide for that. It is written in Spanish so use a browser that does the translating for you, if needed.

While you work on your phone, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has a device with the same issues as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

Repair is War on Entropy!