Оригинальный сообщение: Song Huang ,
This may sound stupid, but bear with me. There’s a fine mesh covering the earpiece. It often gets completely clogged with dirt and oils over time. This blocks the sound waves coming from the speaker. If you moisten and suck out the dirt (yeah, some might get in your mouth) this may fix this. I am not joking, search the web and you’ll find that this has been a common issue for older phones.