This mostly pertains original iphones, as they have been around longer but it may also help those with the new garbage 3G.
I recently noticed that my speaker was much less than a friends new model. The ringtone and keyboard clicks were at a much lowered volume. Anyway I was sitting at work when I noticed that some of the holes at the bottom covering the speaker looked different and upon closer inspection I found some of these holes to be plugged with debris. We have pressured air here and I used that on the bottom and I could see a lot of debris blowing out. The volume improved tenfold! I think that many owners like myself keep their iPhone in their pocket and thats where the problem starts with lint. Hope this helps.
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I recently noticed that my speaker was much less than a friends new model. The ringtone and keyboard clicks were at a much lowered volume. Anyway I was sitting at work when I noticed that some of the holes at the bottom covering the speaker looked different and upon closer inspection I found some of these holes to be plugged with debris. We have pressured air here and I used that on the bottom and I could see a lot of debris blowing out. The volume improved tenfold! I think that many owners like myself keep their iPhone in their pocket and thats where the problem starts with lint. Hope this helps.
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